Why Lebron James needs (the right kind of) carbs

http://online.wsj.com/articles/why-lebron-james-is-suddenly-skinny-1408388466

The world is abuzz with Lebron James' recent decision to undertake a low carbohydrate Paleo diet and the more svelte physique that followed.  While the aesthetic change to his decision is readily apparent, the performance ramifications wait to be seen.  As someone who has used principles of the Paleo diet for my own personal nutrition as well as those of my clients for the past 5 years, I am familiar with the ins and outs of this type of nutrition program.  While paying more attention to the quality of one's diet can improve performance, cutting carbohydrates is not always the best idea for someone in a sport like basketball.

The type of fuel a person uses is dependent on the type of activity they partake in.  Someone who sits at a desk and does low level physical activity throughout the day doesn't need a large amount of carbohydrate because this type of activity predominantly uses fat.  If this person were to get up and sprint on and off for 30 seconds at a time they would shift to burning glucose, which is what the body turns carbohydrates in to.  In the event this person decides not to eat carbohydrate and still tries to perform physical activity that requires glucose from carbohydrates, they will eventually "bonk".  This means they will not be able to produce energy fast enough to keep up with demand.  While they will be able to make glucose from non-carbohydrate energy sources, the body cannot produce it fast enough to keep up with the demands of a sport like basketball.  My prediction: Either Lebron starts eating carbohydratess or his game will suffer.

So if slashing carbohydrates isn't going to give a performance advantage, how can following principles of the Paleo diet improve athletic performance?  To better understand how this works, it's important to get a basic understanding of how the immune system works.  I promise this won't get too technical.  Monocytes are essentially immature white blood cells, they roam around the bloodstream like a couple of high schoolers looking for something to do.  Just like a high schooler, they have no specialized skill because they haven't received instruction yet.  When monocytes encounter an area of the body in need, they quickly receive a PhD in what needs to be done from the environment and differentiate in to a more specialized type of cell that can carry out a more specific task in that tissue.  This could be to identify invaders, fight an infection, or repair damage from exercise.  An important point to understand in this process is that it is often inflammation that gives the monocytes the instructions and, thus their PhD in what to do.  Once a monocyte has been given instructions on what to do by a certain tissue, they are essentially useless to any other tissue in the body.

Neutrophils are another type of white blood cell, the most numerous.  Neutrophils act and move quickly to sites of inflammation to help battle invaders by engulfing them, secreting antimicrobial proteins that help digest invaders, and increasing inflammation to signal there is an infection.  The function of monocytes and neutrophils is important to understanding how the principles of the Paleo diet can improve athletic performance.

The Paleo diet avoids refined sugars/processed foods, grains, legumes and dairy and replaces them with fruit and vegetables.  Many people elect to eat large quantities of meat as well, but since most people eat large quantities of meat regardless of whether they eat a Paleo diet or not, we'll skim past that part(FYI, I recommend a moderate level of meat consumptions).  The gluten in grains and casein in dairy are two proteins that can increase inflammation in the GI tract.  An inflamed GI tract could hijack monocytes that would be better served helping you recover from exercise induced damage to muscle tissue.

In addition to tying up monocytes that could help recovery, GI inflammation also increases intestinal permeability to lipopolysaccharide(LPS).  LPS drives the immune system nuts and induces insulin resistance in muscle and fat tissue to preserve glucose for the immune system.  Since insulin sensitivity is the primary dictator of an athletes ability to replenish glycogen stores after training or competition, causing insulin resistance at any point in the recovery process can be bad for performance.

One final piece of the puzzle is how neutrophils respond to refined sugars.  Ingestion of large amounts of refined sugars has been shown to reduce the ability of neutrophils to engulf invaders for up to 5 hours post-ingestion while starches had not effects(1).  While this effect likely has a modest direct effect on exercise recovery, it will have a greater impact on susceptibility to infection which, over the long term, can negatively impact performance by taking an athlete away from training.

While many people attribute the benefits of a Paleo diet to a low carbohydrate content, most of the positive benefits of the diet occur because the quality of the diet changes.  By improving the quality of your diet, you can improve athletic performance by improving recovery through better immune system function.  Furthermore, if you participate in a sport that primarily relies on glucose for energy, cutting carbohydrates will have a deleterious effect on performance.  My prediction for Lebron James is that he will either increase his carbohydrate intake during the season, or you will see at least a minor drop in his performance.

Does the Paleo diet cure X?

http://www.examiner.com/article/jack-osbourne-high-fat-low-carb-ketogenic-paleo-diet-helps-multiple-sclerosis

The link above is one of many anecdotal pieces of evidence that has shown significant health improvements from a Paleo diet.  The health conditions that are purportedly improved by a Paleo diet range from inflammatory conditions such as Rheumatoid Arthritis, digestive problems such as Irritable Bowel Syndrome, neurological problems such as Multiple Sclerosis, and the number one killer in the United States: heart disease.  Are these pieces of evidence enough to state that the Paleo diet cures any of these conditions?  Absolutely not, we are eons away from a scientific consensus on what causes these problems, let alone what we can do to fix them.  Does this mean that the Paleo diet isn't the answer?  Nope.

Science is a wonderful thing, but not a necessity for something to be true.  Science is the process we use to come to a consensus on a topic such as this because it eliminates all alternative explanations.  Truths aren't made by science, they are identified with it.  It very well could be the case that many of our modern ills are directly attributable to the lifestyle we live.  Many of the problems that have plagued human civilization throughout history can be directly attributed to things we have determined to be "progress".  The formation of cities and towns is certainly progress, but that doesn't mean that communicable disease and the rapid spread of infection isn't a product of that progress.  As Lord Helmet told us many years ago, there is an up side and a down side to every Schwartz.

This is where the evolutionary approach to health enters the picture.  You've got X, will the Paleo diet help?  help maybe, but cure?  No.  Why?  The evolutionary approach to medicine isn't a diet.  There are many aspects of today's life that are quite novel to modern humans.  Never having to go hungry, never having to experience extremes in temperature, being able to sit on your butt all day long and still procure ample food, not having to succumb to bacterial infections due to antibiotics, and the onslaught of chronic stress we experience today.  The current food environment is certainly a drastic shift to our species, but it is one of many issues that may not jibe with our genetic code.

When you look at the epidemiological research, it is universally accepted that things like poor sleep, a diet high in processed food and calories, high levels of stress, long periods of inactivity, and infrequent intense physical activity are all aspects of modern life that are problematic to health.  When you look at modern day hunter gatherers who live a lifestyle that completely eliminates these traits, we see insignificant levels of the diseases that plague us such as Cardiovascular disease, Type 2 diabetes, Cancer, and even Depression.  Multiple studies are coming out showing what many of these poor lifestyle traits do to us at a genetic level, strengthening support that many of our issues are caused by our current lifestyle.  From a scientific perspective, this doesn't prove anything. Besides, let's say being born by C-section or having to take a dose of antibiotics to kill a bacterial infection do have some ramifications, is the alternative, aka death, a better prognosis than later obesity or IBS?  Probably not, but knowing how to take steps to prevent or reduce the potential symptoms from those potential outcomes likely lies within the evolutionary approach to health.

Many people can benefit from this information, and waiting for a scientific consensus is not going to benefit most people in this lifetime because it won't likely come in that time period.  Even if the scientific consensus comes, it won't show that the Paleo diet or an evolutionary approach to health cures these problems.  What it will show is that many of our current health problems may be caused by a modern lifestyle, but that doesn't mean doing some diet for 3 months will allow you to go back to business as usual.

Paleo and remission from Multiple Sclerosis: Is there something there?

http://www.examiner.com/article/jack-osbourne-credits-low-carb-paleo-diet-for-70-lb-weight-loss-managing-ms

Chad Vaccarino of the music group A Great Big World and Jack Osbourne, son of Ozzy Osbourne, have both seen dramatic improvements in the symptoms they experience from Multiple Sclerosis.  In the video above, Chad discusses his history with treating the disease from taking pharmaceuticals that he felt made him sicker to his use of the Paleo Diet, which he claims has thrown him in to remission.  Chad's Paleo story began when he watched the widely viewed TED talk given by Dr. Terry Wahls, a physician who went from wheelchair-bound to perfectly ambulatory after researching and implementing what is now known as the Wahls' Protocol for Multiple Sclerosis.

While stories like this seem to be fairly common in the internet world, many people are rightfully skeptical.  As the physician in the video states, there is no evidence that diet will help with Multiple Sclerosis.  This is true from a purely scientific standpoint, but therein lies the rub.  There is no hard scientific evidence that the Paleo diet is effective for Multiple Sclerosis, yet here we have 2 people who have absolutely nothing to gain from telling you that it helped them saying that they are essentially symptom free.  As I have mentioned before, however, science doesn't make truths, it identifies them.  What I mean by this is that a lack of evidence doesn't mean something isn't true, it just means we haven't identified it as being true.  A great example of this is that at one point there was no evidence that the Earth was round, yet it has always been round.

This is where we run in to trouble.  Just like you are unlikely to find a treasure if you aren't looking for it, you are unlikely to identify scientific truths unless you search for them via research studies.  Upwards of 65% of biomedical research is funded by companies who are looking for something that they can patent and, therefore, profit from.  Since you can't patent a diet, there is no financial incentive to study the effect of diet on health.  Despite being incredibly beneficial to us as a society, research in this area is unlikely to be carried out via normal means.  While Dr. Wahls has sent numerous grant proposals to the NIH, she has yet to receive funding.  This is where crowd-sourced funding can be quite beneficial, and where you come in.  If 0.3% of the US population each donated $1 to Dr. Wahls' foundation, she would have enough funding to carry out a clinical trial.

The link below allows you to donate to Dr. Wahls' foundation to help fund her work.  If you would like to donate, that's awesome.  What may seem like an insignificant amount of money to you can be significant if enough people give.  Even if you don't wish to donate, please share this blog article with others so that they may donate to help fund research that is unlikely to be carried out otherwise.  If you donate, donate in Dr. Wahls' name and thank her for her work.  Use the mailing address in the right margin as her address.

http://terrywahls.com/resources/research/

If you are interested in learning more about the Wahls Protocol for Multiple Sclerosis. check out her book The Wahls Protocol.  Also, if you use Amazon to purchase stuff, you can use the smile program and they will donate a portion of your purchase to a charity of your choosing.  Just select The Wahls Foundation as your charity of choice.  This in no way impacts the cost of your purchases.

Some nutritional recommendations are Bolshevik

A recent article making the rounds in Australia and New Zealand attempts to expose the dangers of the Paleo Diet by pointing to scientific advice that just doesn't exist while at the same time pointing to the paucity of clinical trials supporting the diet.  The two primary faults of the article are inconsistent logic as well as utilizing scientific data in a way that it cannot be utilized, both of which combine to make a dizzying array of non-points that make it difficult for a layperson to differentiate fact from fiction.

At the heart of the story is the notion that there is no hard scientific studies showing the Paleo diet to be more effective than the standard diet recommended by most health authorities.  This is not to say there aren't many studies that show a Paleo diet to be more healthy than a Mediterranean Diet for several populations, there are several.  What it says is that these studies do not have enough participants to make a clear determination as to whether the diet is better than what health authorities currently recommend.

In my opinion, this is a valid point.  However, when these same health authorities point to the healthfulness of processed food products such as whole grains, they are using data that cannot be used to make that determination.  One of the inherent problems with nutrition research is that you have studies that are well controlled that can be used to say A causes B. Since these studies are well controlled they tend to have a very small number of participants because they restrict external influences that may affect the results.  Theses are the types of studies that are coveted by scientists, but they are extremely expensive and hard to do and, therefore, quite rare.

On the other side of the coin are studies that can have a huge number of participants but that aren't controlled at all.  No matter how many people you have in these studies, you can never say A causes B because you aren't testing whether A causes B, you are testing whether there is a relationship between the two.  This second type of study is where most, if not all, nutritional recommendations come from.  The problem is, using these studies to say eating X improves health is essentially lying because the studies do not say A causes B or B causes A, they say A and B share a relationship that deserves further testing in a well controlled experiment.

In the very few well controlled experiments that experts use to show whole grains to be healthy, whole grains are compared to refined grains as a control group.  In effect, these studies do not show whole grains to be a healthy part of a diet, it shows them to be healthier than refined grains, which we know to be fairly unhealthy.  Of course, it's difficult to identify which type of study the health authorities are using to refute the Paleo diet in these articles since they don't post any references. 

On the logical fallacy end of things is the point that our ancestors ate seeds of grasses, which is a fair point.  However, comparing a loaf of Pepperidge Farms bread to the types of grains eaten by our ancestors is hardly a scientific comparison.  For one, the traditional way to prepare grains is to soak them, which aids in digestion and cuts back on some of the toxic properties of grains.  Secondly, grinding grains with a mortar and pestle is hardly the same as the modern processing of grains in to bread by machine.

Another logical fallacy in these arguments is that grains are somehow necessary to a healthy diet.  While this is not directly stated in these articles, it is implied by the notion that cutting out grains or specific food groups is detrimental to health.  While the authors like to point out that the diet of our ancestors varied greatly, and many included seeds of grasses(grains), this notion does not in anyway imply that grains are necessary to health.  In fact, many modern hunter gatherer societies don't eat grains and do quite well.

While I agree with many points health authorities make against a Paleo Diet, particularly that a high meat/low carb/low diversity diet is a good idea, I feel these arguments are against the lunatic fringe of those implementing the diet.  A lot of this has to do with earlier iterations of the diet and the now increased availability of the books and sources that promoted it.  Over time, the message that Paleo diet proponents have crafted has become more refined and more scientifically sound.  A great reference for what I believe to be the future of the movement can be found here.  Rather than pointing the finger at macronutrients such as carbs or fat, the modern processing of food and it's effect on the microbiota of humans is implicated.

While I don't think this will quell the influx of experts who argue against the diet, it will certainly make it more scientifically valid.  None of this is to say that a rigid Paleo diet is absolutely necessary for health.  However, making better food choices a majority of the time based on principles identified by the science being generated from principles of evolutionary health can only be beneficial in the absence of hard scientific data that shows one way or another that processed grains, whether whole or refined, are something healthful to eat.  That data, despite the insistence by health authorities, does not exist.

Paleo and Endurance Exercise: The Pendulum hath swung back

One of the more "interesting" things I find with most hardcore advocates of the Paleo or Primal diets is that they love to use the evolutionary template when it suits them and discard parts of it that don't jibe with their preconceived notions of what they believe to be optimal.  I have been guilty of this at times myself.  A couple of great examples are the use of starches in the diet and the predominantly meat-heavy diet they believe our ancestors ate.  There are a couple of great examples of hunter gatherer tribes that eat tons of starches with no ill effects, the Hadza being the most well known.  As far as meat being a huge part of the diet, this is debateable.  What is not debateable is that large fatty cuts of meat were not the norm.  Just because a hunter gatherer didn't discard the fat from a lean animal doesn't mean they ate fat ad libitum in the same vein as bulletproof coffee.  What is also not debateable is that even if they ate a more animal-based diet, they were doing so while also consuming 100-150g of plant-based fiber, something you are unlikely to get with today's vegetables without high doses of supplemental fiber.  This would be highly protective of the microbiome that our ancestors had and makes your bacon and nut butter-based diet not applicable to theirs.

Another great example of ignoring the data comes in the form of eschewing exercise in the aerobic energy pathway.  There are numerous traits that humans have evolved that set us apart from our primate ancestors and make us incredibly adept at endurance running.  You can see this anatomically in the way that we are built as well as physiologically in the way our energy systems operate.  These adaptations include adaptations to the tendons and ligaments that allow for greater forces, enhanced thermoregulation through sweating, glutes that can generate large forces and help stabilize the leg, a pelvis and spine that can absorb and stabilize against greater forces, larger joints surfaces in the lower body to improve shock absorption, and a foot well adapted to generating large forces(1).

A body that can absorb large forces like this, from a walking perspective, is unnecessary.  It's also unlikely that animals that were once our prey were being sprinted down by a much slower animal.  Since some of these adaptations predate modern humans, and weapons used at the time were not sharp enough to pierce the flesh of animals when thrown from a distance, it seems likely that endurance running may have been something that drove the evolution of modern humans.  (For a more thorough rundown of this, I recommend the book The Story of the Human Body by Dr. Dan Lieberman).  In addition, many of the adaptations to endurance exercise that we see in modern research imply that endurance running is indeed important to human health.

There are other benefits of endurance exercise that show great promise in human health, and many of these are separate and sometimes diametrically opposed to resistance/sprint training.  Quite a few of these adaptations are complementary to the adaptations of resistance exercise and affect the brain as well as the cardiovascular and immune systems.  Over the course of the next 2 blogs, I will take a look at the adaptations to both strength training and endurance exercise and how you can practically apply this information to enhance your health.

In the first blog, we will go over what the research shows us to be the beneficial adaptations from strength training and endurance exercise.  Do you eat MCTs or coconut oil for the ketones?  Are you looking to improve your ability to burn fat efficiently?  Is brain performance important to you?  Will a robust immune system improve your quality of life?  We'll take a look at how resistance and endurance training each affect these systems and why ignoring endurance exercise is a mistake.

In the second blog we will go over how we can apply this information to your exercise program.  How much?  How often?  How intense?  What kind?  All of these questions are important and we will cover them all.

Hopefully this series gives you a new appreciation for an exercise modality you have likely been ignoring while following a Paleo or Primal lifestyle.  While strength training and sprinting are both excellent forms of exercise, they do not provide you with all of the benefits you could be getting from a program that includes both of these modalities with endurance training.

The 2am low carb wake up call...

As the Paleo diet becomes more popular and people give it a whirl, it's important to understand that many early versions that were low carb presented problems for some people, especially people who were training hard in exercise modalities that primarily use glucose for fuel such as Crossfit.  One of the more common experiences under this scenario is waking up between 2am-4am, often times with heavy heart pounding.  This phenomenon can be explained and potentially remedied using what we know about blood glucose regulation and what I went over in my last 2 blogs found here and here on allowing the intestine to help the liver with blood glucose regulation.

Now, there is a simple fix, eat more carbohydrates; and you should probably do this over the long term anyway if you are training hard.  There is a solution that you can use during short term low-carb dieting to lose weight or if you want to stick to a low carb diet over longer periods.  But first, let's take a look at what may be happening to wake you up.

The modern Western diet, being high in carbohydrate and low in fiber, relies heavily upon the liver to regulate blood glucose levels.  While it is pretty good at doing it's job, not providing carbohydrates to help it do it's job can make blood glucose regulation difficult.  To help your liver keep pace, glucagon and epinepherine levels rise in the blood to communicate to the liver that it needs to release some of the glucose it stores as glycogen, provided it has stored up enough glycogen from the carbohydrates you consume and made enough glycogen from non-carbohydrate sources.  But what happens if there is not enough glycogen stored in the liver to keep blood glucose above the critical level?

When you are up and moving around, muscles break down glucose in to lactate that the liver can use to make glucose via a process called the Cori cycle.  This likely contributes to blood glucose regulation while you are awake.  The interesting thing here is that epinepherine, more commonly known as adrenaline, causes muscle to break down glucose in to lactate and activates the Cori cycle(1).  As you may know as well, adrenaline also rapidly increases heart rate and the force of contraction of the heart.  Could the 2am low carb wake up call be due to blood glucose levels dipping too low and the adrenals correcting this issue by secreting epinepherine?  This could certainly explain why people get woken up and experience a pounding heart.  If this is the case, there is a simple correction that should remedy the situation.  Remove some of the burden of blood glucose regulation on the liver by allowing the intestine to participate.  In other words, increase your fiber intake.

Most Americans get less than 20g of fiber per day and a person who is undertaking a low carbohydrate diet likely gets less if they are avoiding vegetables.  Bumping this number up to 60g or more could potentially help a person who wishes to maintain a low carbohydrate diet not have to worry about large drops in blood glucose.  Optimally the fiber would come directly from the diet, but you could also take a fiber or resistant starch supplement to get your daily fiber intake up.  Many people are taking Bob's Red Mill unmodified potato starch as a supplement to increase fiber intake, just start with a low dose and space out your intake throughout the day to prevent gas.  You can work up to 4 tbsp per day which adds approximately 32g of resistant starch/fiber per day.

It may take a while to see significant improvements, especially in people who may not have a large amount of bacteria that ferment fiber/resistant starch in to the short chained fatty acids that help the intestine participate in blood glucose regulation.  Be persistent and, most of all, pay attention to what your body is telling you.  Gas tends to be a good thing, but if it becomes painful or smells putrid you may have to take it slower.

Evolution and diabetes part 2: Blood glucose regulation by ancestral humans

In my last blog I went over a study that casts some doubt on the notion that the liver is critical for blood glucose control.  In this study, they found that mice who had their liver blocked from contributing to blood glucose control adapted by shifting that duty over to the kidneys and intestine(1).  The assumption that the liver is king as far as blood glucose control is a fairly widely held concept due to the fact that it can store 100g of glucose and produce glucose from non-carbohydrate sources.  The problem arises when you take in to account that easy access to carbohydrates is a fairly recent phenomenon.  Taken together with other scientific evidence, it appears that the intestine should likely play a larger role in blood glucose regulation than it does today, and the modern diet prevents this from happening.

In this study the kidneys took on a much larger role in blood glucose regulation during times of fasting as the gene crucial for blood glucose regulation increased in expression.  The intestine also saw an increase in expression of this gene, but the total expression of this gene was 50x greater in the kidney.  These results may understate the importance of the intestine in blood glucose regulation, especially in the non-fasted state.

When you compare the diet of ancestral, pre-agricultural humans to that of today, one glaring difference is the fiber content of the diet.  Today, the average human diet contains less than 20g of fiber per day.  In his book The Story of the Human Body, Dr. Dan Lieberman's assessment of the literature points to the consumption of 100-150g of fiber per day by pre-agricultural humans.  This number is in line with what previous research has shown(2) as well as Jeff Leach's experience living with modern day hunter gatherers.  While the difference in fiber intake may not seem important when you consider humans don't absorb fiber, when you look at what it does to the microbiome and the effect it has on blood glucose regulation you can see that it is likely very important.

When bacteria in the intestine break down fiber, they make short-chain fatty acids(SCFAs), specifically butyrate and propionate.  Both of these SCFAs promote intestinal gluconeogensis in complementary ways(3).  Gluconeogenesis is the generation of blood glucose from non-carbohydrate sources and it allows the intestine to participate in blood glucose regulation through the fermentation of fiber by bacteria in the gut.  Interesingly, when gluconeogenesis is shut off in the intestine, all of the metabolic benefits of a high fiber diet are lost despite having a similar microbiome.  So, in a population where people consume low amounts of fiber, the intestine likely has a negligible role in regulating blood glucose.  Ironically, in this population, blood glucose tends to run high.  In a population where fiber is consumed in large quantities, the intestine likely takes on a much larger role in regulating blood glucose.  In this population, blood glucose tends to remain low.  This is not the only piece of the puzzle, however.

There is another issue that arises when bacteria in the intestine don't ferment fiber in to butyrate.  Butyrate is the fuel of choice for cells of the colon(4), but they are able to metabolize glucose as well.  A problem occurs when there isn't enough butyrate for the cells of the colon(Colonocytes), they must rely on glucose as a source of energy(4, 5).  When colonocytes are provided enough butyrate, they break it down in to the ketone beta-hydroxybutyrate which can be further broken down for energy.  When there isn't enough butyrate, they are forced to metabolize glucose which colonocytes break down in to lactate.  Colonocytes cannot metabolize lactate so it is sent to the liver to undergo gluconeogenesis.  In a mouse model of colitis, this is how colonocytes metabolize energy(5).  Unfortunately, glucose is unable to provide enough energy for efficient  gastrointestinal function in this manner(4).

In addition to having an effect on gluconeogenesis by the intestine, SCFAs also stimulate secretion of a hormone called glucagon-like peptide 1(GLP-1)(6).  GLP-1 has several roles in the body, but of interest to our discussion is it's role in insulin and glucagon secretion.  Insulin lowers blood glucose by causing cells to take it in while glucagon causes blood glucose to increase by increasing gluconeogenesis in the liver, kidney and intestine as well as causing those organs to release glucose.  GLP-1 stimulates insulin secretion in a glucose dependent manner, when glucose levels are high GLP-1 stimulates more insulin than when glucose levels are low while it causes glucagon levels to fall independent of glucose levels.  It is worthy to note that carbohydrate consumption also causes GLP-1 to be secreted, but since carbohydrate consumption will cause blood glucose levels to rise, it will cause more insulin secretion than one would see going the fiber route.

People with Type 2 diabetes tend to have a large amount of insulin in their blood, but their cells don't respond to it because they have become resistant.  This causes their blood glucose to run high because insulin can't do it's job of lowering blood glucose.  Since glucagon increases blood glucose and runs high in Type 2 diabetics, it is believed that lowering glucagon levels can help correct the high blood glucose levels associated with the disease.  Metformin, the Type 2 diabetes medicine of choice, works by causing the liver to make less glucose, which causes the same effect as lowering glucagon.  GLP-1 and drugs that mimic it accomplish the same thing, are being used as pharmaceutical therapies, and the result is lower blood glucose levels(7, 8).

The positive effect of administering GLP-1 to improve blood glucose regulation brings up a few interesting questions.  Is the intestine a more important component of blood glucose regulation than we give it credit for?  Is bacterial fermentation of fiber in to butyrate the first step in blood glucose regulation given how important it likely was for blood glucose regulation in ancestral humans?  Finally, is administering pharmaceutical GLP-1 merely restoring an ancient signal from the intestine to the liver saying, "I have your back" with regard to gluconeogenesis and blood glucose regulation?  While we are unlikely to find answers to these questions any time soon, it is very interesting that higher fiber intake is very protective against Type 2 diabetes (9, 10, 11, 12).  Furthermore, people with Type diabetes tend to have more disturbances within the digestive tract than healthy people(13, 14) with the most common disturbance being constipation.

Between the evidence provided above and comparisons of the ancestral diet to our modern one, it seems likely that the modern diet may be presenting an environment that causes blood glucose to be regulated in a way that is not efficient for humans.  Our long history of high fiber consumption likely selected for people who were good at using the fermentation of fiber by resident bacteria as the first step of blood glucose regulation that involved the intestine to a much larger degree than it does today.  The modern diet puts a much larger burden on the liver to make and regulate blood glucose due to the high carbohydrate and low fiber content of the diet.  This provides less fuel to allow the intestine to participate in blood glucose regulation and may be a contributing factor to Type 2 diabetes and the increased occurrence of GI disorders associated with the disease.

Evolution, diabetes, and blood glucose regulation

When practiced appropriately, science can shed a lot of light on some pretty powerful concepts in human health.  To date we have unlocked the human genome, developed some novel pharmaceutical interventions for diseases that were once taking a large toll on society, and begun to understand that we are carrying along an exponentially larger number of bacteria that have a dramatic impact on the way we function.  However, many of the health concerns we see today are not being addressed in the appropriate manner.  Comparing the use of a pharmaceutical drug to no treatment, or placebo, makes perfect sense when you are dealing with a bacterial or viral pathogen, but does it really make sense when the true problem is a poor lifestyle?

When performing science, you are not really trying to prove anything, you are trying to disprove the null hypothesis.  The null hypothesis is the default position, and in the instance of a pharmaceutical intervention against a pathogen it typically means giving some of the subjects a placebo pill to simulate not doing anything.  The problem is, at this point, there is a very large lifestyle component to the vast majority of diseases we are seeing today.  This includes cardiovascular disease, some types of cancer, Alzheimer's, and the topic of this blog, Type 2 diabetes.  If we know that a poor lifestyle largely contributes to these diseases, should the default position be taking a placebo pill and calling it a day, or would it make more sense to have the default condition be changing those lifestyle habits that cause the disease?  I suppose that depends on how you look at what the pharmaceutical intervention is trying to accomplish.

Let's be honest, I've worked in the health and wellness field for 18 years.  When someone is told they need to change their lifestyle or a disease they have is going to progress and they choose not to, they really aren't looking for a solution.  What they are looking for is something that will allow them to continue their poor lifestyle while preventing the damage that their lifestyle causes.  If this is what we are testing for with pharmaceutical interventions for these lifestyle diseases, it only makes sense to have the null hypothesis be the condition where the damage stops.  In other words, the null hypothesis should be the lifestyle that causes no more damage.  That way, when we compare the pharmaceutical intervention to the proper lifestyle group, we have an idea to what extent the drug is actually subsidizing the poor behavior.  When you compare the pharmaceutical drug to doing absolutely nothing other than taking a sugar pill, what would you expect to happen?  The drug will come out looking like it's the cure for something that it's not, which gives the false impression that the person has nothing to worry about.

So what lifestyle should be this default position?  Since these lifestyle diseases are prevalent in Western society, it makes no sense to have the null hypothesis be based on the lifestyle of Westerners.  However, these diseases are not at all prevalent in modern day hunter gatherers who live a lifestyle more in line with the one we spent most of our time evolving under.  This has led many to believe that the null hypothesis, the default lifestyle condition to test against, should be identical to the one we evolved under.

This poses a major problem.  The vast majority of our science has been conducted during a time when the Western lifestyle has been the default condition because that has been the default condition since clinical research has become prominent.  An easy way to understand this is that we have come up with RDAs for nutrients in human health, but these RDAs are only relevant under a Western lifestyle because a Western lifestyle is the condition under which they were tested.  So it is improper to say that the RDA for Vitamin C is the amount of Vitamin C one needs to prevent scurvy.  The proper way to phrase what the science actually shows is that the RDA for Vitamin C is the amount of Vitamin C one living a Western lifestyle during the time of testing needs to prevent scurvy.

Assuming the way we currently do things as it pertains to lifestyle is the default condition can also lead us down the wrong path when we are looking at how our body works.  It has been assumed that the liver is the primary site of blood glucose regulation.  However, this may not actually be the case, it could be that the liver is the primary site of blood glucose regulation in those living a Western lifestyle.  A study looking at blood glucose regulation in mice has shed some light on why this may be the case.

In order to better understand how blood glucose is regulated, researchers studied mice who were unable to regulate blood glucose via the liver.  The liver is considered to be critical in blood glucose regulation, without it we cannot stabilize blood glucose.  As the story goes, we eat carbohydrates that turn in to glucose, the liver stores that glucose and releases it during fasting, and when we are completely fasted, the liver makes glucose from non-carbohydrate food sources.

In the fed state during the study, blood glucose levels were identical between normal mice and mice that were unable to use their liver to regulate blood glucose.  During the fasted state, blood glucose levels dropped initially and ketones went up, but within 30 hours both groups of mice had the same blood glucose level as genetic expression changed in the kidneys and intestine to favor blood glucose regulation by those organs in the absence of the liver(1).  It is important to note that while blood glucose levels were lower in the mice who relied on the kidneys and intestines for glucose production, blood glucose never reached a critical state as the kidneys and intestines utilized ketones for approximately 50% of their energy and were able to provide enough glucose for survival.  In addition, this study found that the kidneys and intestine make glucose out of the amino acid glutamine while the liver uses alanine and lactate.

While it may not seem like this study has any real world relevance since most humans have functioning livers, it does highlight that the liver is not absolutely necessary for blood glucose regulation.  The liver is certainly a large player in blood glucose regulation as it can store approximately 100g of glucose and is capable of making glucose from other sources, but the assumption that the optimal way to regulate blood glucose is through consumption of carbohydrate and storage in the liver is flawed.  At this point we really don't know for sure how to optimally regulate blood glucose, but if we look at some key aspects of the ancestral diet some doubt creeps in.

In my next blog we'll take a look at how blood glucose may have been regulated by ancestral humans and how the drastic change in the way we regulate blood glucose now may be contributing to the increased prevalence of Type 2 diabetes.

Part 2

Evolution, physical activity, and human health

The chronic diseases we see today are often the result of poor lifestyle choices.  Cardiovascular disease, Type 2 diabetes, obesity, cancer, arthritis, depression, and Alzheimer's disease are all considered normal parts of the aging process and are often called diseases of aging.  The problem is, when you look at "less civilized" cultures, particularly modern day hunter gatherers, these diseases either don't exist or are insignificant even in older members.  This has caused many to postulate that the Western lifestyle may be a significant factor in the prevalence of these diseases.

In 2002, Booth wrote a paper going over exercise and gene expression(1).  This paper is a classic in the evolutionary medicine arena because it shined a light on the effect of exercise on gene expression and proposed the theory that genes expressed as a result of physical activity would promote disease in a person who doesn't meet the necessary threshold to activate these genes.  In other words, the lifestyle diseases that are often attributed to aging may be, at least partially, from a deficiency in physical activity.

 

Booth's primary focus was on the notion that physical activity increased muscle mass and fuel utilization, improved cardiovascular function, and improved cellular insulin sensitivity while physical inactivity did the opposite.  Given that lower muscle mass, poor cardiovascular function, and poor insulin sensitivity are either seen in or associated with most of the lifestyle diseases seen in Western culture, it is fair to say that all of these factors may play a role in the relationship between Western disease and physical inactivity.  However, current research adds more to the story.

A review from 2010 discussed the relationship between inactivity and an overly sensitive stress response(2).  Recently, the author of that study was able to identify the physiological change in the brain that come with high levels of physical inactivity.  He found that physical inactivity causes a re-wiring in the rat brain.  Specifically, it causes a more dispersive branching of neurons in the rostral ventrolateral medulla(RVLM), an area of the brain that helps control the stress response(3).  The researchers believe this increased branching is what causes the neurons in the RVLM to be more responsive to stress in physically inactive rats.  While this study has not been repeated in humans, it bears to note that increased sensitivity of the stress response, also called increased sympathetic tone, is also found in many of the lifestyle diseases mentioned above and sedentary behavior is also strongly associated with these diseases(4, 5, 6, 7) and the low grade inflammation that accompanies them(8, 9).

There are other avenues within inactivity physiology that apply to health and are worth mentioning.  During aerobic metabolism, reactive oxygen species(ROS), or free radicals, are continuously generated(10).  Free radicals are molecules with an unpaired electron that serve vital roles in cellular function, but react with healthy molecules within the body and cause oxidative stress when not held in check.  Oxidative stress occurs when free radical generation outpaces the ability of the body's antioxidant defense systems to deal with free radicals.  The body's antioxidant pathways donate electrons to free radicals and help keep free radicals at a healthy level.  As I mentioned in this previous blog, prolonged sitting causes changes in genetic expression that reduce antioxidant and anti-inflammatory pathways and reduce insulin sensitivity.  This would increase oxidative stress which is another physiological factor associated with lifestyle diseases.  In addition, increased oxidative stress leads to higher levels of inflammation which are also associated with these diseases.

Some people attempt to head off oxidative stress by taking antioxidants supplements.  The problem with this is that when supplemental antioxidants are taken and they meet up with a free radical, they donate an electron to the free radical which makes the former antioxidant a free radical, albeit a weaker one.  The antioxidants generated by the body's antioxidant defense system, particularly glutathione, are able to donate electrons to free radicals as well as recharge antioxidants that become free radicals as a result of donating an electron.  This makes the body's antioxidant defense system far more powerful than any antioxidant you can take orally.

What makes this avenue of inactivity physiology particularly interesting is that recent evidence has shown that the average daily energy expenditure of Hadza hunter gatherers is the same as Westerners when controlled for body size despite the physical activity level of the Hadza being greater(11).  Since a person at rest is primarily utilizing aerobic metabolism, it is safe to assume that both groups are either generating the same number of free radicals or the Westerners are generating more based on their larger size alone.  On top of this, the increased level of sedentary behavior associated with the Western lifestyle could potentially induce higher levels of oxidative stress through a reduction in antioxidant gene expression while the physically active lifestyle of the Hadza may promote health by keeping free radical levels at an appropriate level.  Since the Western lifestyle diseases discussed earlier are also associated with high levels of oxidative stress and hunter gatherers like the Hadza rarely experience them, it makes you wonder if shutting down these pathways contributes to the Western lifestyle diseases.  In other words, a deficiency in physical activity may in fact be a strong contributor to the lifestyle diseases that are prevalent in Western cultures for many physiological reasons.

Logical fallacies aganst a Paleo diet

At this point in time, there is not likely a more controversial diet than the Paleo diet.  Advocates tout how much better the vast majority of people who undertake it feel as well as the numerous health improvements, primarily autoimmune diseases that go in to remission, that people see under a Paleo diet.  Critics argue that there wasn't a single Paleo diet, per se, and that grains, legumes and dairy have been a major part of a healthy diet for many years.  The question then becomes, "So who is right?"  Therein lies the problem, the argument between the advocates and critics really isn't about who is right, it's about whether or not the science supports the Paleo diet or not.  The problem here, in my opinion, is that those criticizing the diet set the bar at a level that won't likely be met for some time, but that doesn't mean the supporters of Paleo are wrong.

I've been in many discussions with people who basically believe the Paleo diet is poppycock.  I've argued with trolls on the internet, I've had physicians tell me it's complete BS, and I've read Paleofantasy in utter surprise that a higher level scientist would make several errors in logic in a published piece.  I will spare you the arguments on straw men such as the Paleo diet is low carb or that it's basically a bacon orgy.  I will focus on the basic assumption that the Paleo diet views grains, legumes, and dairy as foods that are likely to be problematic for more people than they are healthful.

The first error in logic that comes up in a typical argument is that the onus of proof is on the person making the claim.  This is a typical argument from a person who is a contrarian and just likes to argue.  If I say I don't believe those 3 groups of food are healthy for people to consume and you say that I'm wrong, it seems to me that both of us has made a claim that needs backing up.  At this point, both should provide their reasoning behind their claim, this is how science works.

This isn't typically how it goes, however, and when they ask for evidence they go straight for the gold standard.  They say you must provide a randomized controlled clinical trial(RCT) in order for them to take your claim seriously, which is setting the bar higher than they should because, as far as I am aware, there exists no such study that backs up either side of the argument.  They then point to a few epidemiological studies or studies comparing whole grain consumption to refined grain consumption to show that grains are perfectly fine to consume.  None of them actually show this because epidemiological studies can't show causation and comparing whole grain consumption to refined grain consumption shows nothing about whether grains are a healthy food choice, only that whole grains are better than refined grains.

This brings up a couple of important points about applying logic.  First, just because there is no evidence that something exists doesn't mean it doesn't, especially if it hasn't been studied in depth.  At some point I'm sure there was scant evidence that the Earth was round or that bloodletting was a stupid idea, but both ended up being true anyway.  There was likely anecdotal evidence for both long before there was an RCT, that's how science works, observation followed by testing.  Nevertheless, I'm sure the countless people who died or whose illness was prolonged from bloodletting would have loved to know that there was an argument to be made against it.  About 10% of our entire medical system is based on RCTs, the rest is based on anecdotal evidence, epidemiological studies, and other forms of evidence that would not suffice critics of the Paleo diet unless they were using it to argue against the diet, but who have likely benefited from medical care that was based on that inferior data.

Another point about logic is that it should be applied universally.  Many critics of Paleo like to point out that just because something wasn't eaten in Paleolithic times doesn't mean that it's bad for you, which is actually true.  In the same sense, just because we have been eating something for 10,000 or even 50,000 years and it hasn't killed us before we've reproduced doesn't mean it's good for us, only that it doesn't affect reproduction and therefore won't place selective pressure on our species.  This means it won't thin out the herd and force a change in our species, it may simply become a nuisance that people have to deal with as they get older and damage accumulates.  Arthritis doesn't kill you, but I imagine anyone who has lived with it for decades would be happy if they didn't have to live the rest of their lives with it.

My final point is about arbitrary points in time.  It is not logical to assume that anything that happened prior to the RCT is BS or that anything we are eating now that doesn't cause an immediate cardiac arrest is healthy.  There weren't RCTs in ancient Greece when modern humans began to realize that the Earth wasn't flat, but it turned out to be true anyway.  Most people aren't interested in finding out exactly what the science says, most are interested in what is most likely the truth and this sometimes requires going outside of what the science specifically says and extrapolating from other areas of science to fill in the holes.  In the same way that not all foods that we eat now are healthy, not all new foods are bad just because we didn't eat them at some arbitrary point in time.  We are constantly changing and some new foods that weren't available in the Paleolithic such as olive oil and broccoli have turned out to be quite healthy for us.

So why do I follow a Paleo diet?  I don't really follow a Paleo diet, I follow a Paleo template.  I limit grains, legumes and dairy because I feel there is enough evidence that those foods contain proteins that are not digested well by us that make their way in to our colon and mess with our microbiome.  This is likely a dose dependent issue and genetic variability as well as epigenetic factors likely play a role so certain foods may be perfectly fine for some people and not so fine for others.  Until there is a way to tell for sure, I will limit those foods, but I still eat them on occasion.  You can hedge your bets by eating a diet high in vegetable matter, moderate in meat, and high in fermentable fibers that the healthy bacteria in your gut use to sustain themselves.  This should, in theory, also allow you to get away with eating things that are not necessarily healthy for your microbiome as it bolsters the good guys so that the bad guys don't take hold.  At least that is what I have come up with based on the evidence, if any new evidence comes to light I will certainly take it in to consideration.

5 important resources for undertaking a Paleo diet

I've helped many people shift from a conventional diet to a Paleo-based diet.  More often than not, the information is easy to understand and you can get substantial buy-in by providing a little science, but the problems begin when you get to implementation.  In this blog I will go over 5 resources that people should use to help implement a Paleo diet.

1)A thorough plan

Before you take any step, do yourself a favor and get together a solid, detailed plan.  If you were going to drive to Florida or plan a vacation anywhere, you wouldn't just wing it because winging it is likely to lead to failure or at least a less than optimal experience.  Look at shifting from your standard diet to the Paleo diet as a journey.  Where are you going?  How are you going to get there?  Are there any potential pitfalls along the way?  Do I need anything to make this an enjoyable journey?  Fortunately, enough people have undertaken this path before you that you likely don't have to pay someone to help you.  You can buy a book, or just pop online and read other peoples' experiences.  There are a few standard issues that people run in to while implementing a Paleo diet, and most of these issues are due to poor planning.  What do you do if you're out eating with friends?  What should you have in the house to snack on in case you get hungry?  Are there any strategies you can use to reduce the amount of time you spend in the kitchen.  Fortunately, these problem have been encountered by other people and can be answered pretty simply if you sit down and develop a detailed plan rather than just say you're going to do a Paleo diet for 30 days and wing it.  In my next blog I will discuss how to come up with a detailed plan and provide a sample one I made for a client.

2)Nuritiondata.self.com

One of the biggest pitfalls people encounter when "going Paleo" is that they end up neglecting certain nutrients that are contained in a group of foods they may not particularly enjoy.  Nutritiondata.self.com is a good way to identify the nutrients you may not be getting and determine which foods you should add in to your diet to get them.  Once you sign up, you can enter the foods you eat every day and look at an analysis of which nutrients you are getting and which you may be missing out on with your food choices.  From there, you can use the tools section and search for foods high in the nutrients you are deficient in to help make a more healthful diet.  I find www.nutritiondata.self.com indispensable when developing a diet for someone and a great value, especially since it's free.  It's also a good way to develop a diet for clients while using their existing diet as a template, that way the change is not as severe.

3) Good food storage containers

One thing we can never have enough of in my house is food storage containers.  Whether we are cutting up vegetables for the next few days, packing lunch, or making extra chili for the following week; we always seem to run out of food storage containers in short order.  One of the biggest changes when switching to a Paleo diet is that it is not very convenient from a food prep standpoint.  Rather than spend more than an hour every day preparing food, we tend to spend an hour 2 times a week cutting and prepping food and then storing leftovers from each nights dinner in the freezer for the following week so that we are always prepared.  A ton of food storage containers in multiple sizes is crucial for cutting back on prep time.

4)An activity tracker

Activity trackers are very useful places to store and look at data that may be of interest to you.  I've used a Fitbit One on a daily basis for the past 2 years.  While I am using it to motivate and compete with my clients, I initially used it to look at how my lifestyle affected my health.  I found a few things including coffee and dairy that I eventually removed from my diet since both seemed to be effecting my sleep in a negative way that also caused my morning fasting blood glucose to be a little high.  I removed them and saw a fairly substantial improvement after a couple of weeks so I kept them out and make sure not to do other things that may negatively affect my sleep if I do partake in either.  Another benefit I find from the Fitbit is that clients who tell me they are doing everything they can to lose weight are often sitting around for hours at a time or only getting 6000 steps per day.  If they wonder why the diet isn't working for weight loss and they are getting 6000 steps per day, I can tell them the problem isn't the diet, it's the couch.  I go over a bunch of the ways you can use your Fitbit One sleep data in this blog.

5)Spices

In terms of nutrient density, nothing beats spices.  Ounce for ounce, spices are a far greater source of many essential nutrients than any other foodstuff on the planet.  They also contain a ton of phytonutrients that provide many benefits outside of those found in the essential nutrients.  For example, turmeric, a spice used frequently in middle eastern cuisine, has a potent anti-inflammatory effect and activates stage 2 cell detoxification.  Also, garlic contains a special form of vitamin B-1 called allithiamine that is 50x more bioavailable than the thiamine version of B-1 found in nearly every other food.  B-1 is crucial for carbohydrate metabolism, adrenal health, and is a nutrient likely lacking in any Paleo diet that doesn't utilize copious amounts of sesame seeds or tahini.  You can check out why B-1 is important and signs you may be deficient here.  While fresh spices are best, dried ones should be added to oil first to help release the essential oils.  You really can't go wrong with any spices, I like to rotate mine daily so that I get a myriad of benefits that I didn't get when my diet was fairly plain from a spice standpoint.  Another added benefit to using spices is that they can be a way to get plant matter in to your diet if you react to FODMAPS because they are consumed in far lower doses than whole plants and vegetables.

Why your Paleo diet may not be so healthy

I love the logic behind the Paleo diet and the many health problems that people have reversed by undertaking it.  People have reversed autoimmune diseases and Type 2 diabetes, lost tons of weight, and drastically improved their overall health in many ways from fatigue and pain relief to just being happier.  While there is a lot going for the Paleo diet, I feel many may be making errors in logic when formulating their own personal Paleo diet.  In this blog I'll take a look at the primary logical fallacy I see in Paleo world.

Start the story from the beginning

When we think of our ancestors, we tend to think of our immediate ones that looked like us, talked like us, and ate diets very similar to ours.  The problem with thinking this way is that it starts the narrative halfway through the story.  The story doesn't begin with a somewhat modern human with an ape face chasing down game, it begins with a primarily herbivorous primate that was likely incapable of hunting or attaining any meat outside of scavenging dead carcasses.  Ok, you got me, it actually begins much further back with a single celled organism, but since their diets didn't consist of food as we look at it today, what they ate doesn't really provide us with concrete evidence as to what we should eat...or does it?  More on that later.

So here we have an herbivore who is competing for food against other herbivores in a constantly changing climate that is ultimately responsible for all of the mass extinctions save for the dinosaurs.  Being able to eat different foods is not a novelty of an animal living in this world, it's a survival necessity.  When competition was tough or the climate changed the foods that were available, having fallback foods that are not typically parts of the native diet can be crucial to survival.  While scavenging the remains of dead carcasses may be the first thing that comes to the mind in Paleo world, another one is the consumption of underground storage organisms, also known as roots and tubers.

To get at roots and tubers, you need a couple of traits that these early primates likely didn't have.  First, they would have needed the intelligence to be able to identify them as potential food sources, despite the food portion being located underground.  Second and more importantly, it would require the use of tools to dig them out.  Using a stick to dig a tuber out of the ground was likely one of the first steps in the use of tools, even if it's not it certainly predated the making of hunting tools such as spears, atlatls, and bows.  So here we likely have a point in time where a small offshoot of the primates started consuming these fallback foods when the components of their primary diet were not available.  However, being fallback foods, they still weren't the bulk of the diet when all food was available.

Fallback foods and evolution

Over time our diet likely changed immensely as our ancestors evolved in to something more human-like, but we started as an herbivore and that is likely what our diet should be made mostly out of...plants.  When you look at fallback foods, most of them have some sort of importance in to what we evolved in to because those that didn't eat these fallback foods likely evolved in to something else or disappeared altogether.  This doesn't mean that a fallback food that helped get us to where we are should become the staple portion of the diet.  In fact, if you are arguing for Paleo you really can't do that.  Grains and legumes began as a fallback food and were likely necessary to get us where we are now.  This doesn't mean that ad libitum grain consumption should be your goal, and in the same way it doesn't mean ad libitum meat or protein consumption should be either.

To clarify what I mean, I have to go in to the microbiome, teh collection of bacteria located in your GI tract.  When a person switches from an entirely plant matter diet to an entirely animal matter diet, as would happen when the dry season or winter comes, the microbiome changes drastically and very quickly(1).  As this happens, your microbiome is adapting to the foods that are available and changing what is happening in your body by changing it's inputs, and changing inputs changes outputs  What we tend to see in this scenario is a change from mostly carbohydrate/fiber fermenting bacteria to mostly protein/amino acid fermenting bacteria.  This change, in theory, will lead to increased intestinal permeability as the butyric acid used to seal up and repair tight junctions between cells in your digestive tract won't be produced as it is a byproduct of bacterial fermentation of fiber in your colon.  This, in turn will increase systemic inflammation which sounds like a bad thing, but in the context of low food availability it is actually a beneficial trait.

With increased systemic inflammation, comes insulin resistance.  In today's world this is bad because we have unfettered access to all types of foods, but several thousand years ago it probably activated the thrifty genotype that is associated with more efficient fat storage and more energy extraction which is beneficial when food is low.  This process is described by Jeff Leach in a blog on his website discussing the effect of a low carb diet on the microbiome and another one where he discusses the Paleo diet and obesity located here.  In the grand scheme of things this got us to where we are today, but that doesn't mean that it doesn't contribute to the problems we see in a completely different food environment.

If we flash forward many moons, grains and legumes likely had the same impact on farmers.  Here we have an easily storable source of nutrients that can last through even the longest winter, and it just so happens that they have proteins that humans have difficulty breaking down.  The result, a steady flow of substrate to bacteria in the colon that ferment amino acids and increase insulin resistance in a time where it is beneficial.  Again, beneficial when food is scarce, not so beneficial when food is plentiful. 

Fighting microbes with microbes

Here we have some compelling evidence that a Paleo diet that is 90% meat with a few veggies may not be the best in terms of health.  Further support for this notion comes from another blog by Jeff Leach that identifies that it may not be high levels of protein so much as it is low fiber consumption that is the problem with a typical high meat Paleo diet(2).  Fermentable fibers, since we can't digest them, provide substrate to the colon that will increase the amount of bacteria that ferment fiber there,  This will also crowd out some of the amino acid fermenters, and also creates an acidic environment that amino acid fermenters can't survive in.  This is not to say that you cannot eat high levels of protein, only that the smart way to do it is to make sure you are getting enough fiber to support the microbes in your gut.  Something I find interesting is that people who undertake ketogenic diets typically don't achieve success unless they limit protein.  The assumption is that the excess protein gets converted to glucose in the body, but this doesn't necessarily have to be the only thing at work, your microbes could play a significant role here as well.

Would you like some partially digested plant matter with your steak?

I know it sounds like I'm beating the Jeff Leach horse to death, but he is studying the effect of many variables on the microbiome, and since he's hanging around with hunter gatherers, he provides other evidence that the microbiome is critically important and ad libitum meat consumption may not be the best idea.  Jeff's experience with a group of Hadza hunters is very eye opening.  When these hunter gatherers killed and field dressed an impala, they did something that would make most of us cringe; they tore open the stomach, washed their hands with the partially digested contents, and cut up parts of the raw stomach and ate them(3).  While this may seem a little kooky to you and I, maybe they know something that we don't.  Maybe there is some undesired consequence to unfettered protein consumption just as there is some undesired consequence to grain and legume consumption.  Perhaps "innoculating" themselves with the fiber fermenting bacteria of an herbivore provides some level of protection against large shifts in the microbial composition of the gut.  Who knows, but I can't imagine they do this just for the fun of it.

Conclusion

Creating a diet based on evolution requires applying the same type of logic throughout the entire story.  Grains and legumes as fallback foods were likely beneficial when they were needed, but in a completely different food environment I think there is strong evidence that they are not so good.  Of the two, legumes contain fiber as well as hard to digest proteins, so they are likely less problematic than grains.  I think it is 100% true that our ancestors ate these foods, just as I am 100% sure that seasonal food availability likely led to times where animal flesh was the primary source of nourishment in the diet.  This doesn't mean that it is optimal from a health perspective, only that it was necessary to get us to where we are.  Mass consumption of grains and legumes as well as an uber-high protein diet may not be in your best interest if health is your primary concern and you have unlimited availability of fruits and vegetables.  This isn't to say that protein isn't necessary, it is.  It's merely to point out that eating pounds of bacon, sausage, and steak every day coupled with mass consumption of nut butters and flours likely isn't healthy, especially if fiber in the diet is low.  While people like to point out that correlation doesn't equal causation when looking at protein consumption and health, that doesn't mean there is no causation there, simply that we can't imply it from the data.  I guess you could just eat the partially digested contents of the cow who made up your hamburger, I'll just hammer some veggies and resistant starch.

The Human's guide to being human: Evolution and adaptation

If you look at the 3 aspects of your genome, you can see that each allows adaptability but over differing time periods and scales.  Your coding genes don't change during your lifetime so they don't help to make you, as an individual, adapt to the environment.  What they do is allow the species, as a whole, to change as the environment changes and provide a framework for adaptation to occur.  The epigenome gives you some ability to adapt to the environment by changing the way genes are expressed, but you are still restricted to what you can do by your coding genes.  Finally, the microbiome allows you to adapt to the environment quickly based on the microbes you come in to contact with and the food that you eat.

If you truly think about it, adaptation is going on everywhere here.  The environment in your gut causes your microbiome to adapt which changes the internal environment, your internal environment makes your cells adapt via the epigenome, and the species as a whole adapts via evolution as certain coding genes make some people more successful at interacting with the environment than others and those people pass those genes on to future generations.  But what is the difference between adaptation and evolution?

The difference between evolving and adapting

There is a distinct difference between evolving and adapting.  Adapting occurs in individuals and is brought about by the environment affecting change on that individual.  A good example of this can be seen in weightlifting.  When you begin lifting weights and don't wear gloves, you develop calluses on your hands.  This makes the skin stronger and less likely to rip the next time you lift weights.  You are basically adapting to the stress being placed on your hands by making the skin a little stronger for next time.  The adaptation doesn't stop at the hands, over time your nervous system becomes more efficient, you lay down more muscle fibers to make you stronger, and your bones become more dense as a load is placed through them and/or the muscles you are using cause deformations of the bone which signals them to get thicker.  These are all adaptations and they make you better at lifting weights.

Evolution, on the other hand, doesn't happen to an individual, it happens to a population.  Over the course of your life you adapt to the environment, but you don't evolve.  The species as a whole, or a sub-population of the species, evolves over long periods of time as it becomes better suited to the environment, but individuals within the population are not evolving, they are adapting.  I only bring this up because many ill-informed people discredit evolution by saying that it cannot be true because we don't see humans actively evolving in to monkeys.  The human species evolves, individual humans adapt.

Let's take a look at an example of each.  Let's say we have a population of mice where half are white and half are green.  If we take this population of mice and place it in an environment where the ground is covered in green flora, the green mice would have an advantage over the white mice because predators would be less likely to see the green mice.  As a result, the number of white mice would begin to dwindle and the green mice would begin to outbreed the white mice, leading to most of these mice being green.  Let's say some of the white mice were exceptionally smart and were able to realize that looking for food at night allowed them to procure food AND reproduce without being killed by some of their predators.

This would allow a few white mice to still be kicking around when an ice age came about and the white mice became better suited to being able to hide in this new environment where the ground was mostly white.  As a result, you would see the white mice begin to outbreed the green mice and eventually become more numerous.  The change from equal parts white and green mice to mostly green mice to mostly white mice is evolution of that species.  The individual white mice who were able to adapt to the environment by hunting at night allowing that segment of the population to stick around long enough for the white color trait to be beneficial, that is adaptation. 

How evolution affects our health

Evolution is important to understand because the environment our ancestors lived in caused our species to evolve.  This is not the same thing as saying the environment molded us to become well adapted to it, that never happened.  It's also not the same thing as saying we were perfectly adapted to any particular environment from our past, as far as evolution goes there is no such thing as perfect and environments change quickly which can cause formerly beneficial traits to quickly become a liability, as seen above.  I don't think anyone would argue that our cravings to devour high sugar/high fat/salty foods is no longer beneficial to us in an environment where food is plentiful and food companies exploit these cravings to get us to buy and overconsume their products.

This also doesn't mean that we cannot be better suited to a different environment, it just means that if we are not doing well in a particular environment we can look at the environment our ancestors lived in and compare that to the environment we are currently in to identify aspects of the new environment that we may not be well suited for.  Since we are individuals, adaptation is our primary concern because we do not evolve, but remember that our ability to adapt is constrained by our genome, which was developed through evolution.  There is no doubt that the environment we are in is drastically different from the one most of our ancestors adapted to and the human genome as a whole evolved in, and science is beginning to allow us to peel back the onion and take a look at this from a genetic perspective.

Cha-cha-cha-changes

The environment our species evolved in for the vast majority of time on this planet was devoid of processed foods, high in physical activity, and low in sedentary behavior.  Being a couch potato is a relatively new option for individuals of our species since our ancestors actually had to procure their food through more physical means than calling Domino's.  Furthermore, our bodies are not well suited to experiencing stress the way we do today.  For most of our time on the planet, stress has been intermittent and resolved very quickly.  If you encounter a bear in the woods and it wants to make you lunch, you either get away or become lunch, you may become more conscious of bears in the area but you don't lament about it for a month.  Stress was more acute back then, it's more chronic now.

Chronic stress is a more recent physiological problem that's been brought about through society.  All of these things have an impact on our internal physiology and, thus, the environment our cells are in.  It's not too big of a reach to think that these lifestyle factors can impact our health by causing our cells to adapt in a way that isn't healthy for us.  New studies on the way lifestyle decisions impact genetic expression are beginning to open up our eyes to the way our lifestyle choices impact our health.  In my next blog we will look at how our new environment is clashing with our old physiology and what the research shows about how this affects our health.

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Meat-based diet and inflammation? Makes sense from an evolutionary perspective

A new study in the journal Nature set the Paleo blogosphere ablaze last month.  This study looked at the effect of diet on changes in gut bacteria and was discussed in my Health Research Recap found here.  I went over how I agree that a diet that focuses on meat is likely not the best choice if your goal is to be healthy.  In this blog I am going to expand on this topic using the evolutionary template to theorize why this happens.

One of the more interesting aspects of the study in question, found here, is that gut bacteria switched rapidly when going to the extremes of diet.  In my opinion, this is a testament to how important a diverse array of bacteria in the gut is to maintaining metabolic flexibility.  Humans can thrive on a wide array of diets and the ability of bacteria in the gut to respond to quick changes in the availability of food from the environment is what makes us metabolically flexible.  From an evolutionary perspective this makes sense because once our ancestors left Africa, the most likely to survive would have been the ancestors who could adapt to changes in the types of food that were available due to seasonal changes in the climate.

As Summer leads to Fall and Fall leads to Winter, the availability of fruit and other foods that were preferred by our ancestors who remained in Africa would not have been available in more seasonal climates during a time when you couldn't just order takeout.  To adapt, they likely needed to consume fallback foods that were available in a wintery climate during that time of year.  This would include meats and root vegetables whose availability would change less with the seasons.  With this change from a diet high in fruits and vegetables to one with a proportionally smaller amount of these foods and a higher proportion of animal flesh, you are changing the substrate that the bacteria in your gut can ferment from mostly fermentable carbohydrates to amino acids.  This, in turn, should change the proportion of bacteria in the gut, favoring the types of gut bacteria that ferment amino acids and scaling back the type that ferment carbohydrates.  Could there be some evolutionary benefit for this switch?  I think so.

As the diversity of available food reduces during the winter time, there would be a benefit to extracting more energy out of that food.  Most people believe that carbohydrates and protein contain the same amount of calories per gram at 4 calories, but this is not true.  In a bomb calorimeter, carbohydrates average 4.2 calories of energy per gram while proteins average 5.65 calories per gram.  Some of this increased energy content is due to the nitrogen content of protein, which humans don't use for energy.  Even if half of the extra energy is from nitrogen, that still leaves an extra 17% more energy in protein per gram than carbohydrates.  This is huge when food becomes scarce.  One of the first things one notices as they implement a low carbohydrate diet is constipation.  Maybe this delay in food transit through the digestive tract allows us to absorb more of that energy or it gives bacteria in the colon more time to ferment amino acids that make it there, providing more energy than we can extract on our own.

On top of the potential for extra extractable energy contained in protein, there is the inflammation associated with the bacteria identified in the study.  While our current food environment makes this a bad thing, in the face of food scarcity, this inflammation may be beneficial.  Inflammation is associated with insulin resistance and obesity, two conditions associated with the theoretical thrifty genotype that is more likely to experience these conditions.  Perhaps the inflammation associated with this change in gut bacteria is expressing these thrifty genes to a greater extent and allowing the host to get by with less food.  In other words, the inflammation these types of bacteria create functions as a signaling molecule to the host, letting their body know that it's time to be thrifty and more efficient with cellular energy consumption and storage as the types of available food declines.  This inflammation coupled with moderate to high carbohydrate consumption could improve fat stores during the end of fall as the wintery season approaches and begins to take hold.

We can compare this to what we see today in Type 2 diabetes.  In Type 2 diabetes, people become insulin resistant which causes their blood glucose to rise.  What we see in people with Type 2 diabetes is an eventual spilling of fatty acids in to the blood stream during this process.  This is due to the extremely high levels of blood glucose we are able to attain today with the types of foods that are available in addition to the fact that we are able to exceed our ability to store fat.  Who knows how this process would play out as it did back when our ancestors were moving out of Africa searching for food and being on the low end of their fat storage capabilities.  If it plays out in a similar fashion to the beginning stages of Type 2 diabetes, it is likely that they experienced an enhanced ability to accumulate body fat, a beneficial effect when going in to a season where carbohydrates won't be available.  What we are now seeing with Type 2 diabetes could potentially be the consequences of our past environment selecting traits that were advantageous at the time that are now no longer advantageous.  A recent study in the journal Nature indicates that this may be so.

The study looked at people of Latin American descent and identified a gene associated with Type 2 diabetes that is very prevalent in that population(approximately 50%) called SLC16A11.  This genetic variant alters fat metabolism and causes an increase in cellular fat levels.  People with one copy of this variant are 25% more likely to develop Type 2 diabetes while people with two copies are 50% more likely to develop it when compared to people without this variant.  All of this science mumbo jumbo is nice, but the science behind this pales in comparison to where this gene likely came from; Neanderthals.

This is extremely interesting because Neanderthals left Africa much earlier than we did and those that were more adapted to efficiently storing fat were far more likely to be successful in environments where food sources were seasonal.  Much of the Neanderthal anatomy was suited to cold weather because they had experienced it for millenia before we made our way out of Africa, it only makes sense that their physiology would be optimized for that environment as well.  If this is one of the thrifty genes, perhaps as their diet changed moving in to winter, so did their gut bacteria,.  This, in turn, may have increased expression of this gene, as well as others, which would make them more "thrifty" and, thus, better adapted to their environment via improved fat storage.

Another piece of potential "evidence" comes from those undertaking low carbohydrate diets.  It is common knowledge that low carbohydrate diets aren't typically effective for fat loss when protein intake is high.  The conventional thinking is that this is due to protein causing insulin secretion as well as the ability of certain amino acids to convert to glucose and raise blood glucose levels.  However, it is interesting that high protein intake in the face of low fiber intake causes such a dramatic shift in the composition of gut bacteria given that the vast majority of  low carbohydrate diets tend to be high in protein and low in fiber(Atkins diet).  While a much more gradual shift in the availability of foods is more likely, the ability to adapt quickly would be highly beneficial.

Overall, I think there is a lot of evidence that supports the notion that a diet that is primarily meat, potentially even grass-fed beef, may cause inflammation due to increased protein consumption changing the landscape of the host's gut bacteria.  There appears to be a large benefit to the host through this process.  You have to be careful with what you can generalize this to, however.  I don't believe this indicates that moderate meat consumption is bad, and the ratio of meat to fiber is probably a much bigger determinant of this effect as is the ability of the host to digest protein.  Protein consumption, per se, is not the problem.  The ability of undigested protein to make it's way to the colon where the types of gut bacteria that can ferment amino acids can act on it is the chief concern.  In the absence of high carbohydrate consumption, this inflammation may even be benign.

Preliminary results from the Human Gut Project indicate that people who consume a Paleo diet tend to have higher levels of bacteria that are associated with inflammation, but most of these people have fewer complaints related to inflammatory conditions.  I do think this points to a more moderate approach to meat consumption than most people undertaking a Paleo diet implement for the simple fact that most overconsume protein from meat and nuts.  However, this doesn't vindicate the consumption of protein from vegetable sources.  In fact, given that a lot of these proteins are difficult for humans to digest, especially grains as well as soy and other legumes, they could potentially amplify this effect, especially when fiber intake is low.  Since vegans often rely on protein powders rather than whole food sources to fulfill their protein needs, they are essentially consuming high doses of protein that is more likely to become problematic, even at lower total protein intakes  Therefore, consuming concentrated sources of harder to digest proteins is not a great idea if you are looking to control inflammation, especially if you are also consuming large amounts of carbohydrates as is typical of the vegan diet.

Book Review: Last Ape Standing

One topic that is both controversial as well as difficult to write about is human evolution.  For some reason, some people don't feel evolution pertains to us.  In fact, as recently as 2012, less than half of the United States believed that humans evolved either with the assistance of, or in the absence of, a God.  This is fairly troubling given the number of scientific discoveries and medical therapies that are used by everyone today that would not be possible without the study of human evolution.  Evolution is the central tenet behind biology, so much so that trying to "do" biology without evolution would be like trying to fly a plane without the principles of flight.  Medicine is not possible without biology, so one can safely conclude that medicine is not possible without evolution.  The reason that human evolution is so controversial, and also why it is so difficult to discuss, is that it is far from settled.  What Chip Walter does with his book Last Ape Standing is discuss the available evidence and form a story for how we got to where we are today.  He does a fantastic job of doing this.

From the beginning of the book, Chip makes you feel quite comfortable with his knowledge base on the topic.  He fills you in on how evolution works through natural selection and why the argument that evolution is a random event therefore humans cannot be involved in the process is flat out wrong.  What you've become is far from a mistake, you are the product of nearly 4 billion years of the environment on Earth engineering you to become something that can succeed at life in that environment by being born, maturing to the point you can pass on the genes that were passed on to you by your parents, and the same cycle repeating for your offspring.  In fact, humans downright thrive on a planet where most organisms just struggle to stay alive long enough to pass on their genes.  Who you are now is no more of a mistake than a car having 4 wheels or a plane having 2 wings.  Sure, there is the potential that there is a better way, but we don't have it yet.  A great example of this is similarities in body plans between water dwelling mammals and fish.

If you compare a land mammal to a fish, there is not a clear similarity between their body plan.  Sure, both have 2 eyes, 1 mouth, and a few other similar characteristics, there are quite a few differences.  Probably the most obvious is that fish have fins, flippers, and tails while land mammals do not.  However, mammals that live in the ocean tend to have all 3 or at least 2.  This is because to be successful in the water, one would require these traits to be successful.  This is no random mistake, if you don't have a way to move to get food which helps you make it to your reproductive years to pass on your genetic material, you're a goner.

With that basic understanding of evolution, Chip brings you on a journey as to why we are the most successful primate, and why our other human cousins are no longer here.  He takes you on a ride to explore the human family tree and the traits of those who came before us and some who were around alongside us for a while.  The fact that we are the last one standing is a testimony to not only those traits that solely belong to us, but the traits that our forebears passed on that make us better adapted to the environment we are in.  Sure, our brains are far more advanced than any other that came before it, but it would not have been possible to shape that brain had we not come up off all fours, moved from the trees to the savanna, began scavenging food sources high in Omega 3 fatty acids, and eventually began cooking our food.

Many factors apparently played out to make the human brain develop the way it has.  Fasting causes cell growth to slow down in every way except for brain cell growth, which increases in times of food scarcity.  Our brains are extremely rich in the omega 3 fatty acid DHA that can be found in fish and organ meats, but is not efficiently attained from plant sources.  Finally, cooking food makes many nutrients available that we were unable to get to before we cooked food, particularly in meat.  Cooking food gives our digestive systems a break and digestion, particularly in other primates that need to break down fibers that we can't, is an expensive process from an energy standpoint.  When resources don't need to be directed to digestion, they can be directed to brain development, another expensive process.  This is called the expensive tissue hypothesis and is covered in the book.

Another important concept to human development covered in the book is called neoteny. 
Compared to other primates, we are born much sooner, develop much slower, and as a result, develop bigger and better brains.  While humans and chimpanzees have nearly identical coding genes, our genes are expressed differently.  Put another way, it's not the genes, it's how they are used.  And how genes are used is dictated by the environment the organism is in.  This is what epigenetics and evolution is all about.  Chip gives an excellent example of this when he discusses a chance encounter by an anthropologist and a tribesmen who believed a herd of water buffalo in the distance were a type of insect.  Since this tribesman's village was in the dense jungle, he never developed the ability to comprehend long distances such as those he was experiencing on the wide open plain they were standing.  Since the tribesman was never exposed to that type of environment, the genes that would allow him to comprehend that environment in his brain were never expressed, so he never developed teh abiity to process that type of information.

In a similar light, Chip theorizes that one of the reasons we are still here is possibly because we left Africa when the time was right.  Other human species left Africa much earlier than us, but because they were unable to successfully adapt to their environment, or because they adapted to that environment and the environment quickly changed, we took over.  Neanderthals left Africa long before us and became adapted to much colder climates than we were at the time.  Theoretically, they should have been more suited to the climate and environment of the more northern latitudes that we began creeping in to as they had been there longer, but somehow we either out-competed them for resources, killed them off, or simply bred with them until they folded in to us.  An interesting point that Chip makes is that they were unlikely to be able to communicate at the level we could because of the structure of their skull.  They likely communicated, but probably not in as sophisticated of a manner as we could.  With communication comes the sharing of ideas, the ability to cooperate to attain food, and culture.  With all of that, comes creativity.

Toward the end, Last Ape Standing goes over how cooperation and culture are 2 constructs that helped us become who we are.  He also discusses some very interesting ways in which some of our behaviors that are seemingly unrelated to our environment that may be a product of our environment.  He discusses a theory that people prefer younger looking mates because it would be an indication of the concept of neoteny mentioned earlier.  Younger looking people give the impression that they are aging more slowly, and aging more slowly, if it leads to better brain development, would be a desired trait.  He also discusses how both schizophrenia and autism may both be products of the brain misfiring during development, essentially neoteny gone wrong.  Again, timing is everything.

Honestly, I could have gone on and on about so many of the things that I pulled out of this book.  I can't think of another book that is under 300 pages that I pulled so much quality information from.  It's hard to hold my attention but this book managed to do it, so much so that I read it in 3 days.  This review could easily have been 3-4x as long as it was, but I have a felling Chip Walter wouldn't want me plagiarising his book on my blog.  I highly recommend anyone who wants to learn about what got us here to buy this book.  It is well written at a level most people with a high school education can understand.  Once I get done with a couple of other books that I just bought, I will buy Chip's earlier book Thumbs, toes, and tears: And other traits that make us human.