In a recent article that hit most every newsroom last week, red meat kills people again. Here is a link to one of the articles (1) and here is a link to the actual study (2). The headlines that hit the newsstands were along the line of, "Red meat increases heart disease!" and things along that nature. If the rate that nutritional information does a flip flop doesn't normally give you vertigo, it will today. In an article published less than a week later, researchers note that an increase in L-Carnitine is protective in people who have just experienced a heart attack (3). Before I show you why you should not rely on the news media to dictate your lifestyle choices, let's look at what each study showed.
In the first study, researchers compared the effect of L-Carnitine supplementation between meat eaters to non-meat eaters. In meat eaters, bacteria in the gut fermented L-Carnitine in to TMAO, a chemical known to accelerate atherosclerosis while this effect was non-existent in non-meat eaters. Since L-Carnitine is high in red meat, researchers believed that constant red meat consumption led to changes in gut flora that promotes an environment beneficial to creation of TMAO. So, excessive red meat consumption leads to higher levels of bacteria that convert Carnitine to TMAO and this can increase atherosclerosis. Check!
The second study was a meta analysis (Large study evaluating many studies) and found that using L-Carnitine was beneficial in the recovery from a heart attack. People who used L-Carnitine were less likely to die from any cause, were less likely to experience arrythmia, less likely to experience angina, and had smaller infarct size than those who did not use L-Carnitine. So, Carnitine conveyed a benefit to the person using it, specifically for heart health.
These 2 contradictory studies highlight a couple of problems. First, the headlines that state, "Red meat increases heart disease" are wrong. Having a specific type of gut flora that may be found in meat eaters would indicate you shouldn't take L-Carnitine supplements. If you don't eat tons of red meat you are unlikely to have gut flora indicative of the people in this study that had a problem with TMAO. Next, by looking at the study we can find the limitations of what the study can say. One thing of note was that this study did not control for veggie intake. What if the benefit of being vegan wasn't that you are not eating red meat, but that vegetable intake is high? A meat eater that eats a lot of vegetables would have very different gut flora than a meat eater who eats none. Maybe the vegan diet is beneficial because of the high vegetable intake, not because of a lack of meat. This is one of the reasons the Synergy Wellness Program recommends a large diversity of foods. A larger diversity of foods allows the bacteria in your gut to be diverse, preventing pathogenic bacteria from being able to grow to a capacity that could impact your health.
One of the problems with getting your science information from the popular press is that they seem to ignore what a study shows as well as the limitations study design put on what you can extract from a study. When you see an article that one week shows coffee to be bad for you, then the following week find one that says it's bad for you, more often than not the problem isn't that the data is conflicting it's that people are ignoring the fact that certain types of data are not appropriate for drawing conclusions. Even when the data is appropriate, the title of the article is meant to grab your attention, not be scientifically accurate. Keep this in mind whenever you are looking at "science" in the popular press.
Showing posts with label Myths. Show all posts
Showing posts with label Myths. Show all posts
Wednesday, May 14, 2014
Thursday, September 19, 2013
Why counting calories doesn't work
The food issue of Scientific American came out yesterday and they have a pretty cool spread on how and why counting calories doesn't work. Below is a video going over some of the very basic science.
Why Calorie Counts are Wrong
As a strength and wellness coach I have seen the argument, time and time again, that in order to lose weight people need to eat less and exercise more. This quantitative approach fails on so many levels that I thought it prudent to write a blog article on why it fails. Before we delve in to the specific reasons why, I think it's important to first set down a framework for how the human body works. From there I will go over why counting calories doesn't work and what you should focus on to lose weight effectively.
We do not need to discuss the biology of this in great depth to grasp a very simple concept. What causes the secretion of hormones is genes. In fact, every biological process occurs via genes. A perfect example is alcohol. In order to make alcohol you need water, sugar, and yeast. The water is the medium in which the yeast convert sugar in to alcohol. The yeast do this because they contain genes that direct the processes that cause the fermentation of sugar in to alcohol and water is required for this process. If the genes weren't there, the yeast would do nothing. If the water and sugar weren't there, the genes would do nothing. If you put the yeast in a pail of gasoline and oil it would do nothing. Genes are a set of instruction for what an organism will do under certain environmental conditions, or signals. If the proper signals are not sent to the genes, they do nothing.
In much the same way, you burn fat under the proper environmental signals. This is largely dictated by the hormonal environment within your body. Making it an even more complex situation, we burn fat and glucose through separate, intertwined processes. At no time are you ever burning 100% fat or 100% carbohydrate. Even if you ate no carbohydrates, your body can still make glucose which is how carbohdyrates enter the glycolytic(carbohydrate burning) energy systems anyway. If you ate no fat you would simply use body fat to fuel fat dependent energy systems.
The energy system that is predominantly used is largely dependent on the environmental signals you send, which are dictated by lifestyle factors including sleep, stress, exercise, diet, and how each affects your hormonal profile. Ignore these factors and not only will you not burn fat, you will set yourself up for failure by producing a hormonal environment primed to drive your appetite through the roof and store as much of the energy you consume as possible. So while you are essentially a machine, you are far too complex of a machine to be broken down in to a simple, archaic energy in/energy out system.
A good analogy for this is a hybrid car. The calories in vs calories out mentality is that if the car won't move, all you need to do is put more fuel in to it, regardless of type. However, if the car won't move because it is out of gasoline, you cannot pour electricity in to the gasoline motor because it cannot use electricity as it's energy source.
Removing these foods for an extended period of time not only reduces your craving for them, it helps put you in a better hormonal environment to burn fat. Frequent consumption of these foods wrecks your metabolism by negatively affecting your cells' sensitivity to insulin and leptin, two very important hormones. If it were simply a matter of calories this shouldn't be an issue, but it's a big one. It's also why once you pop you can't stop and the primary reason you can't eat only one.
If you buy in to the importance of genes for human health, it isn't too far of a stretch to realize that our gut bacteria should be a main concern. These bacteria help us in many ways by helping train and control the immune system, manufacturing nutrients, transporting ions, helping heal intestinal damage, and this is merely the tip of the iceberg. There also appears to be a line of communication between the brain and the gut. This is a 2 way line of communication that appears to be through the vagus nerve(2), a part of the autonomic nervous system which regulates minor things like respiration, heart rate, and blood pressure.
Changes in gut bacteria have been attributed to so many diseases that one may be suspicious of all the things healing the gut could potentially help. People with autism, adhd, anxiety/depression, Type 2 diabetes, heart disease, you name it. With regard to obesity, there is a clear relationship. While there are more than 10,000 different strains of bacteria in your gut, most of that bacteria belongs to 10 species. Of those 10 species, the ones that appear to be the most important to human health are bacteroidetes, firmicutes, and bifidobateria.
Specifically, with regard to obesity, there appears to be two strains of bacteria that are consistently different between obese and lean people, bacteroidetes and firmicutes. Obese people tend to have fewer bacteroidetes and more firmicutes than lean individuals. This relationship is so powerful that in mice, when mice with sterile guts are given the bacteria from lean humans they remain lean and when they are given the bacteria from obese humans they become obese. If you place these mice together in cages and give them the proper diet the obese mice become lean(3) because the obese mice eat the lean mice's bacteria(aka poo).
Many other studies have shown that swapping the gut bacteria between lean and obese mice causes the mice to take on the form of the mouse whose gut bacteria they were given. In all of these experiments, calories were kept exactly the same. One of the primary factors noted for this phenomenon is that the gut bacteria in obese mice extract more energy from food which provides an energy surplus to the host. This means that while the calorie count is the same, the gut bacteria liberate more energy for the host which in turn causes more calories to be absorbed.
I have not seen any evidence that suggests that saturated fat is implicated in altering the gut bacteria in obese people. While it is true that obese people tend to eat more saturated fat, they also tend to eat more processed foods high in sugar and avoid fruits and vegetables. One of the more troubling developments over the past 40 years is that people avoided saturated fat and swapped in processed, high sugar foods which do have a damaging impact on gut bacteria composition. This scenario has played out the way it would in a petri dish as bad bacteria crowd out good ones because the bad ones are fed and the good ones starved.
Being a fitness professional, I should be towing this line if I was doing what's right for my pocket book. If I want to do what's right for my clients, I will help them alter their lifestyle in a way that will foster genetic expression that is optimal for weight loss. This doesn't involve buying supplements, starving yourself, and exercising with me 6 days a week. It involves eating the proper foods and staying off their butts more than sitting on them, something I discuss here. Exercise is merely icing on the cake.
Why Calorie Counts are Wrong
As a strength and wellness coach I have seen the argument, time and time again, that in order to lose weight people need to eat less and exercise more. This quantitative approach fails on so many levels that I thought it prudent to write a blog article on why it fails. Before we delve in to the specific reasons why, I think it's important to first set down a framework for how the human body works. From there I will go over why counting calories doesn't work and what you should focus on to lose weight effectively.
From hormones to genes to environmental signals
When you look at how the body works, you can see fairly easily how counting calories and focusing on burning them fails. Systems within your body talk to one another via hormones, also known as chemical messengers. For example, when you consume a meal, nutrients get digested and eventually enter your bloodstream. These nutrients, in turn, cause the secretion of hormones to help utilize and store these nutrients. When you exercise, hormones are also released that help dictate the fuel you use. In fact, there isn't a time in the day when you are not secreting some level of many hormones. However, while your hormones are affecting how you feel, how much energy you have, and whether you are actively using energy or storing it for later use; what you do throughout the day will also affect those hormones.We do not need to discuss the biology of this in great depth to grasp a very simple concept. What causes the secretion of hormones is genes. In fact, every biological process occurs via genes. A perfect example is alcohol. In order to make alcohol you need water, sugar, and yeast. The water is the medium in which the yeast convert sugar in to alcohol. The yeast do this because they contain genes that direct the processes that cause the fermentation of sugar in to alcohol and water is required for this process. If the genes weren't there, the yeast would do nothing. If the water and sugar weren't there, the genes would do nothing. If you put the yeast in a pail of gasoline and oil it would do nothing. Genes are a set of instruction for what an organism will do under certain environmental conditions, or signals. If the proper signals are not sent to the genes, they do nothing.
In much the same way, you burn fat under the proper environmental signals. This is largely dictated by the hormonal environment within your body. Making it an even more complex situation, we burn fat and glucose through separate, intertwined processes. At no time are you ever burning 100% fat or 100% carbohydrate. Even if you ate no carbohydrates, your body can still make glucose which is how carbohdyrates enter the glycolytic(carbohydrate burning) energy systems anyway. If you ate no fat you would simply use body fat to fuel fat dependent energy systems.
The energy system that is predominantly used is largely dependent on the environmental signals you send, which are dictated by lifestyle factors including sleep, stress, exercise, diet, and how each affects your hormonal profile. Ignore these factors and not only will you not burn fat, you will set yourself up for failure by producing a hormonal environment primed to drive your appetite through the roof and store as much of the energy you consume as possible. So while you are essentially a machine, you are far too complex of a machine to be broken down in to a simple, archaic energy in/energy out system.
A good analogy for this is a hybrid car. The calories in vs calories out mentality is that if the car won't move, all you need to do is put more fuel in to it, regardless of type. However, if the car won't move because it is out of gasoline, you cannot pour electricity in to the gasoline motor because it cannot use electricity as it's energy source.
Appetite and food reward
Another reason that calories in vs calories out doesn't work is because it fails to address appetite. Appetite is dictated by hormones as well as something called food reward which directly impacts hormone secretion. The food reward system is very complex but involves the same processes and areas of the brain that drug addiction affects. Basically, certain foods hit the reward center of your brain hard and generate a sense of pleasure we like. This means that, over time, we will actively seek out these foods, especially when we are hungry.Removing these foods for an extended period of time not only reduces your craving for them, it helps put you in a better hormonal environment to burn fat. Frequent consumption of these foods wrecks your metabolism by negatively affecting your cells' sensitivity to insulin and leptin, two very important hormones. If it were simply a matter of calories this shouldn't be an issue, but it's a big one. It's also why once you pop you can't stop and the primary reason you can't eat only one.
It's all in the genes, and most of them aren't yours
Now that we have a thorough understanding behind the general concepts of how genes impact biology, it becomes important to realize that most of the genes responsible for the biology going on in your body right now do not belong to you. Most people have heard of their gut bacteria, but I don't think they truly understand the scope of how important these little guys are. From a shear numbers standpoint, the bacteria in your gut outnumber the cells of your body 10 to 1. This not only means we are only 10% human, it also means that the amount of genetic material contained within the bacteria in our gut outnumbers that within our cells by a factor of 300(1).If you buy in to the importance of genes for human health, it isn't too far of a stretch to realize that our gut bacteria should be a main concern. These bacteria help us in many ways by helping train and control the immune system, manufacturing nutrients, transporting ions, helping heal intestinal damage, and this is merely the tip of the iceberg. There also appears to be a line of communication between the brain and the gut. This is a 2 way line of communication that appears to be through the vagus nerve(2), a part of the autonomic nervous system which regulates minor things like respiration, heart rate, and blood pressure.
Changes in gut bacteria have been attributed to so many diseases that one may be suspicious of all the things healing the gut could potentially help. People with autism, adhd, anxiety/depression, Type 2 diabetes, heart disease, you name it. With regard to obesity, there is a clear relationship. While there are more than 10,000 different strains of bacteria in your gut, most of that bacteria belongs to 10 species. Of those 10 species, the ones that appear to be the most important to human health are bacteroidetes, firmicutes, and bifidobateria.
Specifically, with regard to obesity, there appears to be two strains of bacteria that are consistently different between obese and lean people, bacteroidetes and firmicutes. Obese people tend to have fewer bacteroidetes and more firmicutes than lean individuals. This relationship is so powerful that in mice, when mice with sterile guts are given the bacteria from lean humans they remain lean and when they are given the bacteria from obese humans they become obese. If you place these mice together in cages and give them the proper diet the obese mice become lean(3) because the obese mice eat the lean mice's bacteria(aka poo).
Many other studies have shown that swapping the gut bacteria between lean and obese mice causes the mice to take on the form of the mouse whose gut bacteria they were given. In all of these experiments, calories were kept exactly the same. One of the primary factors noted for this phenomenon is that the gut bacteria in obese mice extract more energy from food which provides an energy surplus to the host. This means that while the calorie count is the same, the gut bacteria liberate more energy for the host which in turn causes more calories to be absorbed.
Building a proper microbiome
For the most part, the types of bacteria found in your gut are determined in your first few years. Whether you were born vaginally or via C-section, whether you were breast or formula fed, and whether you were kept in a completely sterile environment or had frequent exposure to dirt and bacteria when you were a baby will dictate the types of bacteria in your gut. Once your gut is populated, the proportion of each strain of bacteria is largely dictated by diet. In the study on mice that were given human gut bacteria, a diet high in fruits and vegetables and low in saturated fat led to the more desirable lean gut bacteria while a diet low in fruits and vegetables and high in saturated fat led to the obese gut bacteria. From the research it appears that the more desirable gut bacteria tend to feast on the fiber and polyphenols found in fruits and veggies(4, 5).I have not seen any evidence that suggests that saturated fat is implicated in altering the gut bacteria in obese people. While it is true that obese people tend to eat more saturated fat, they also tend to eat more processed foods high in sugar and avoid fruits and vegetables. One of the more troubling developments over the past 40 years is that people avoided saturated fat and swapped in processed, high sugar foods which do have a damaging impact on gut bacteria composition. This scenario has played out the way it would in a petri dish as bad bacteria crowd out good ones because the bad ones are fed and the good ones starved.
Conclusion
The video posted above goes over why calorie counts are wrong, but that is besides the point. Even if they were accurate, focusing on calories in vs calories out will never be a successful way for people to deal with weight loss. If more people focused on what they should eat rather than how much, they would be in a much better place right now in terms of health as well as proper weight maintenance. The research has been pointing in this direction for quite some time now, but by the time it reaches clinics and fitness professionals it may be too late for some.Being a fitness professional, I should be towing this line if I was doing what's right for my pocket book. If I want to do what's right for my clients, I will help them alter their lifestyle in a way that will foster genetic expression that is optimal for weight loss. This doesn't involve buying supplements, starving yourself, and exercising with me 6 days a week. It involves eating the proper foods and staying off their butts more than sitting on them, something I discuss here. Exercise is merely icing on the cake.
Thursday, August 8, 2013
The popular media. misinformation, and heart disease.
During a routine physical, former President George W. Bush discovered he had a blocked artery in his heart earlier this week. The following day, he had a stent placed in the artery to open the blockage. Watching the NBC Nightly News' description of the event, I found myself to be dumbfounded. Below is a list of key points from the news broadcast.
This certainly adds to the confusion I get when I tell people they don't really need to concern themselves with the amount of cholesterol they eat unless they have a genetic condition called familial hypercholesterolemia. Familial hypercholesterolemia is found in 1 out of every 500 people so it is certainly not a common condition. It will also be interesting to see whether or not the former President is put on statins, despite having normal cholesterol levels. People with familial hypercholesterolemia and people with a previous heart attack are the only people I would recommend take a statin, but that's just what the research shows and I'm not a doctor. That makes the point moot.
A more common problem with dietary research isn't with how the research is conducted so much as the way it is reported. The popular media loves to report results from epidemiological research as fact. These types of studies cannot prove cause and effect, they can only identify relationships that can be further studied with better research. The primary problem lies within the fact that most people get their information from the popular news media and not from peer reviewed journals. When the media reports this stuff, it sticks because everyone has heard it and it becomes established fact even though it has never been proven scientifically. Then, physicians get on television and keep the BS rolling. Is it any wonder how we are so misinformed on diet?
- President Bush is an avid exerciser
- He exercises 5 times a week for at least 30 minutes
- His cholesterol is normal
- Eating a low fat, "heart healthy" diet is your best protection
What you believe about nutrition could be wrong
The medical correspondent, Nancy Snyderman, MD, as well as host Lester Holt bantered about how even someone living a seemingly healthy lifestyle is not immune to the ravages of heart disease. What struck me as strange is that the notion that the recommendations for heart health are pretty much bogus never entered anybody's mind. Of course there is a huge genetic factor involved here as well as the stress involved with leading the free world for 8 years. After all, his father has heart disease and held the same job for 4 years. I have no problem with this fact. However, I do take issue with the recommendations being untouchable, especially if someone can pretty much follow them word by word and still get a blockage.Exercise-Not the cat's meow
For one, exercise is great and is something everyone should do for a multitude of reasons. As for reducing your risk for heart disease, reducing the amount of time spent being sedentary is far more important than exercising. This should be common sense, but to put some numbers behind it, 30 minutes of exercise performed 5 days a week is 2.5 hours out of a total of 168 hours in the week. That's 1.4% of the week, it doesn't even seem plausible that this amount of time could counteract being a slouch on the couch for the other 98.6%.High cholesterol is an overrated risk factor
The fact that his cholesterol is normal is also interesting for most people, but isn't very surprising. Approximately 50% of heart attacks occur in people with normal or low cholesterol. That didn't prevent Dr. Snyderman from referring to the blockage as a cholesterol blockage. I wonder why they don't refer to them as calcifications since the plaques that form the blockages are 50% calcium and only 3% cholesterol.This certainly adds to the confusion I get when I tell people they don't really need to concern themselves with the amount of cholesterol they eat unless they have a genetic condition called familial hypercholesterolemia. Familial hypercholesterolemia is found in 1 out of every 500 people so it is certainly not a common condition. It will also be interesting to see whether or not the former President is put on statins, despite having normal cholesterol levels. People with familial hypercholesterolemia and people with a previous heart attack are the only people I would recommend take a statin, but that's just what the research shows and I'm not a doctor. That makes the point moot.
Low fat does not mean low risk
The notion that the low fat heart healthy diet isn't actually healthy to the heart has been unraveling over the course of the last 5 years. Not only has it been determined that saturated fat and cholesterol are not that bad for you, replacing these foods with processed, low fat foods high in carbohydrate is worse. This has been the de facto dietary advice for a healthy heart for more than 40 years. Talk about digging yourself deeper in to a hole.Science works best when done properly
All of this brings up an excellent point that most people need to understand about science. Science doesn't make truths, it identifies them. When funding for science primarily comes from companies with financial interests in the outcomes of that science, you cannot expect to get unbiased results. A recent article looked at the likelihood of finding positive outcomes in both industry funded and government funded studies, specifically with the pharmaceutical industry. Oddly enough, government funded studies tend to get positive outcomes around 50% of the time while industry funded studies tend to find positive results around 85% of the time. Part of this problem is certainly due to the fact that industry is not required to report results from all of their studies, so they just don't report the negative ones. This is more of a pharmaceutical industry problem, but who do you think is pushing the low fat, low cholesterol BS? I'd go with the folks making the anti-cholesterol drugs.A more common problem with dietary research isn't with how the research is conducted so much as the way it is reported. The popular media loves to report results from epidemiological research as fact. These types of studies cannot prove cause and effect, they can only identify relationships that can be further studied with better research. The primary problem lies within the fact that most people get their information from the popular news media and not from peer reviewed journals. When the media reports this stuff, it sticks because everyone has heard it and it becomes established fact even though it has never been proven scientifically. Then, physicians get on television and keep the BS rolling. Is it any wonder how we are so misinformed on diet?
Thursday, August 1, 2013
A lesson in what we truly know...
I find it humorous when people tell me something is a scientific fact, particularly when it pertains to diet. If you have been paying attention to the popular news media as of late, you may have noticed that cholesterol and saturated fat have been given a mea culpa. After spending more than 30 years being demonized as the cause of heart disease and atherosclerotic plaques, it turns out that cholesterol and saturated fat really aren't that bad for you. Of course, 30 years ago, we knew cholesterol and saturated fat were as bad for society as Keeping up with the Kardashians would eventually become. The problem is that what we knew 30 and even 60 years ago turned out to be wrong, and foolish people continue to pass it around as gospel. Here are some snippets from a paper from 1953 found here.
1) "Atherosclerosis may be readily produced in the rabbit and in the chicken by feeding a diet containing large amounts of cholesterol...while feeding cholesterol to man, or the monkey, has very little effect on the blood even when enormous doses of cholesterol are given."
2) "The cholesterol-fortified diet commonly used to produce hypercholesterolemia and subsequent atherosclerosis in the rabbit...corresponds to about 15 gm of cholesterol in a 3000 calorie diet for a man...Even when concentrating on foods of naturally high cholesterol content, it is difficult to devise a diet to provide, experimentally, as much as 2gm of cholesterol in the daily diet."
3) "That dietary cholesterol is not important for man would be predicted from the fact that the biliary output of cholesterol from the human liver is from 10 to 20 times as much as the daily amount of cholesterol in any diet of natural foods."
4) "Controlled experiments on men clearly show that serum cholesterol changes in direct relation to a change in the total amount of fat in the diet. Both animal and vegetable fats show this effect and the addition or removal of cholesterol from the diet does not change the result. The cholesterol level may fall, however, if the diet is almost exclusively pure fat and is free of carbohydrate."
5) "In the classification of the U.S. Department of Agriculture, by far the largest proportion of the total fats, from 45 to 50 percent in recent years, is "fats and oils as such, excluding butter." This means cooking and salad fats and oils- lard, corn oil, cottonseed oil, hydrogenated vegetable oil shortening, margarine, mayonnaise, etc."
All of this evidence more or less exonerates cholesterol yet it was ignored. In 1977 the government began a decades long attack on cholesterol and saturated fat. The government and AMA recommended that we limit our cholesterol intake and saturated fat intake despite the evidence listed above. Could there be anything worse than that? Actually there can, the person who wrote the above paper was Ancel Keys, the physician whose work was used to form the very recommendations put out in 1977. Despite the fact that there was no evidence that cholesterol was bad the government still recommended limiting cholesterol consumption along with saturated fat. In addition, despite the evidence that most of the fats people were eating in this 1953 study were vegetable in origin, we were told to avoid saturated animal fats and replace them with...wait for it...vegetable oils.
Regardless, Keys still came to the conclusion that we should limit fat consumption as a whole which turned out to be wrong. One of his assertions in this paper that sticks out to me is that controlled studies show a direct relationship between serum cholesterol and fat consumption, but when carbohydrates are kept low, aka fat is upwards of 80% or more of total energy intake, serum cholesterol drops. I wouldn't consider myself a genius or anything, but I find it hard to call something a direct relationship when putting one of the variables at it's highest causes the other one to drop like a rock. Ironically, in this same paper, Keys brushed off a low carb high fat diet as not rooted in reality. Well, in reality, a high fat/low carbohydrate diet is more than likely the diet we subsisted on for millions of years. As an illustration of this concept, I would like you to go home and devise a suitable diet calorie-wise and do so without bread, pasta, cereal or any other processed foods. It's nearly impossible to come up with a 2000-3000 calorie diet that doesn't involve a large number of processed foods OR a lot of animal fats. Since processed foods weren't around a few thousand years ago, I'll let you guess as to whether or not animal fats were a significant part of our ancestor's diet considering Cocoa Puffs certainly wasn't. This is what is so interesting about using an evolutionary template, it not only looks at current data, it looks at whether the current data jives with what the reality was prior to recent history. You know, the type of history that started more than fifty years ago.
So whatever became of Ancel Keys? In 1955 President Dwight Eisenhower survived his first heart attack and decided to begin following the recommendation of Keys. Six more heart attacks later and he finally succumbed to the last one in 1969, how did that advice serve him? As for Keys, he got his picture on the cover of Time magazine in 1961 and Americans soon started snapping in line and following his advice. Fifty-two years later and heart disease is still the leading cause of death in the United States. Whether or not you agree with Keys' conclusions, you have to wonder how long you have to follow advice before you realize it's bad. The truth of the matter is, we obviously don't know exactly what is causing heart disease and diet appears to only be one of many factors involved in it's progression. In addition, the notion that high serum cholesterol is a major causative factors, at least what we consider high, is probably also false. It's simply based on the notion that cholesterol is part of the plaques that form on blood vessel walls. If only someone would have brought that up years ago...Oh yeah, Keys brought it up in the paper cited at the beginning of this blog post. That's the problem, people read something in it's entirety and ignore the parts that don't fit their narrative. Interestingly enough, calcium is also found in the plaques on blood vessel walls yet we were told to supplement to make sure we were getting enough. Recent studies are showing that people who supplement with calcium are more likely to have cardiovascular disease than people who don't. It shouldn't come as any surprise that we seem to be wrong on so many levels, the Earth was flat once upon a time too.
1) "Atherosclerosis may be readily produced in the rabbit and in the chicken by feeding a diet containing large amounts of cholesterol...while feeding cholesterol to man, or the monkey, has very little effect on the blood even when enormous doses of cholesterol are given."
2) "The cholesterol-fortified diet commonly used to produce hypercholesterolemia and subsequent atherosclerosis in the rabbit...corresponds to about 15 gm of cholesterol in a 3000 calorie diet for a man...Even when concentrating on foods of naturally high cholesterol content, it is difficult to devise a diet to provide, experimentally, as much as 2gm of cholesterol in the daily diet."
3) "That dietary cholesterol is not important for man would be predicted from the fact that the biliary output of cholesterol from the human liver is from 10 to 20 times as much as the daily amount of cholesterol in any diet of natural foods."
4) "Controlled experiments on men clearly show that serum cholesterol changes in direct relation to a change in the total amount of fat in the diet. Both animal and vegetable fats show this effect and the addition or removal of cholesterol from the diet does not change the result. The cholesterol level may fall, however, if the diet is almost exclusively pure fat and is free of carbohydrate."
5) "In the classification of the U.S. Department of Agriculture, by far the largest proportion of the total fats, from 45 to 50 percent in recent years, is "fats and oils as such, excluding butter." This means cooking and salad fats and oils- lard, corn oil, cottonseed oil, hydrogenated vegetable oil shortening, margarine, mayonnaise, etc."
All of this evidence more or less exonerates cholesterol yet it was ignored. In 1977 the government began a decades long attack on cholesterol and saturated fat. The government and AMA recommended that we limit our cholesterol intake and saturated fat intake despite the evidence listed above. Could there be anything worse than that? Actually there can, the person who wrote the above paper was Ancel Keys, the physician whose work was used to form the very recommendations put out in 1977. Despite the fact that there was no evidence that cholesterol was bad the government still recommended limiting cholesterol consumption along with saturated fat. In addition, despite the evidence that most of the fats people were eating in this 1953 study were vegetable in origin, we were told to avoid saturated animal fats and replace them with...wait for it...vegetable oils.
Regardless, Keys still came to the conclusion that we should limit fat consumption as a whole which turned out to be wrong. One of his assertions in this paper that sticks out to me is that controlled studies show a direct relationship between serum cholesterol and fat consumption, but when carbohydrates are kept low, aka fat is upwards of 80% or more of total energy intake, serum cholesterol drops. I wouldn't consider myself a genius or anything, but I find it hard to call something a direct relationship when putting one of the variables at it's highest causes the other one to drop like a rock. Ironically, in this same paper, Keys brushed off a low carb high fat diet as not rooted in reality. Well, in reality, a high fat/low carbohydrate diet is more than likely the diet we subsisted on for millions of years. As an illustration of this concept, I would like you to go home and devise a suitable diet calorie-wise and do so without bread, pasta, cereal or any other processed foods. It's nearly impossible to come up with a 2000-3000 calorie diet that doesn't involve a large number of processed foods OR a lot of animal fats. Since processed foods weren't around a few thousand years ago, I'll let you guess as to whether or not animal fats were a significant part of our ancestor's diet considering Cocoa Puffs certainly wasn't. This is what is so interesting about using an evolutionary template, it not only looks at current data, it looks at whether the current data jives with what the reality was prior to recent history. You know, the type of history that started more than fifty years ago.
So whatever became of Ancel Keys? In 1955 President Dwight Eisenhower survived his first heart attack and decided to begin following the recommendation of Keys. Six more heart attacks later and he finally succumbed to the last one in 1969, how did that advice serve him? As for Keys, he got his picture on the cover of Time magazine in 1961 and Americans soon started snapping in line and following his advice. Fifty-two years later and heart disease is still the leading cause of death in the United States. Whether or not you agree with Keys' conclusions, you have to wonder how long you have to follow advice before you realize it's bad. The truth of the matter is, we obviously don't know exactly what is causing heart disease and diet appears to only be one of many factors involved in it's progression. In addition, the notion that high serum cholesterol is a major causative factors, at least what we consider high, is probably also false. It's simply based on the notion that cholesterol is part of the plaques that form on blood vessel walls. If only someone would have brought that up years ago...Oh yeah, Keys brought it up in the paper cited at the beginning of this blog post. That's the problem, people read something in it's entirety and ignore the parts that don't fit their narrative. Interestingly enough, calcium is also found in the plaques on blood vessel walls yet we were told to supplement to make sure we were getting enough. Recent studies are showing that people who supplement with calcium are more likely to have cardiovascular disease than people who don't. It shouldn't come as any surprise that we seem to be wrong on so many levels, the Earth was flat once upon a time too.
Tuesday, February 12, 2013
Cholesterol Screening: A cost to benefit analysis
As more and more employers realize the importance of maintaining a healthy working staff, the number of companies participating in cholesterol screening as part of a risk assessment protocol has increased. There are obvious financial and ethical benefits to having happy, healthy workers. A happier worker is more productive and tends to cost less from a health insurance standpoint. The problem is, will cholesterol screening actually achieve that stated goal? In other words, if I put my worker bees through a cholesterol screening, will this save me some scratch? Let's explore this a little further.
The point of putting workers through a cholesterol screen is to identify those who are at risk for heart disease and/or future coronary events. Once identified, these people will be put on the appropriate therapy to ensure that they avoid experiencing the big one and needing the higher medical costs of dealing with the problem as it arises. In other words, we can all agree that an ounce of prevention is worth a pound of cure. However, let's see if that is actually what we are accomplishing.
Unless you have been hiding under a rock for the past several decades you have heard of statin drugs. Statin drugs are currently the standard of care for treating people with heart disease, despite there being no real evidence that they prevent heart attacks in anyone other than middle aged men who have already had a heart attack. In this very small sample of people, cholesterol screenings are unnecessary because these men are already on statins. For the remainder, let's take a look at what you are buying in to.
Let's say I have a large business with 1000 employees who are not currently on statins and they all sign up for cholesterol screening. The criteria for high cholesterol puts approximately 1 in 3 people in this group, so let's say 333 of your employees are diagnosed with high cholesterol. Most physicians will not prescribe a statin based solely on high cholesterol, so let's assume only 200 of your employees are recommended to take statin drugs. What can we expect to see in terms of results?
If you listen to the way these drugs are marketed, you would realize that statins reduce heart attack risk by 36%, but what does this mean in a way that is pertinent to our discussion? Probably the most clear cut way would be to look at a number that gives you the risk to benefit ratio. In the pharmaceutical world, this is referred to as the number needed to treat (NNT). The NNT is the number of people you would need to treat with the drug in order to prevent 1 person from experiencing the adverse event you are trying to prevent. In other words, in the case of statins, the NNT is the number of people you would need to treat to prevent 1 heart attack. When we look at this number, we get a much clearer picture of what we are getting. The NNT to prevent 1 heart attack varies between 70-250 people depending on the study you look at. When you take in to consideration that this NNT also includes people who have already had a coronary event, the NNT for people that will be undergoing cholesterol screening is closer to 1 in 250. In other words, 249 of the people you are treating with this drug are not benefiting from taking it. Furthermore, you would need to treat all 250 of these people for 5 years with the drug before you would prevent that 1 heart attack.
It is highly likely that every one of the 200 employees you have identified as candidates for statin therapy will receive no benefit from the drug, and you as well as they get to pay for that therapy. In addition, recent research has shown that statin therapy induces diabetes in 1 out of 200 people taking the drugs. So, while you have prevented zero heart attacks you have actually increased your healthcare costs by adding a diabetic to the payroll. By the way, people with Type 2 Diabetes have the same risk of heart attack or dying from heart disease as people who have already had a heart attack. Framed in that context, does that cholesterol screening really sound like something that is going to prove beneficial to your organization or does it seem more like a way to sell you something that is not really going to benefit you at all?
There is, of course, very large healthcare costs associated with someone experiencing a heart attack. You may even hear that spending all of that money treating people with a drug that is not benefiting them in any way may make sense when you look at the cost savings of preventing a heart attack. Ethical considerations aside, this benefit does not exist. High cholesterol isn't even a good indicator of future heart disease. The actual data shows that 50% of the people who die of heart disease have normal cholesterol. In other words, you are financing a screen that has the same likelihood of predicting a heart attack as a coin flip, and investing a large sum of money in it's ability to do that.
The point of putting workers through a cholesterol screen is to identify those who are at risk for heart disease and/or future coronary events. Once identified, these people will be put on the appropriate therapy to ensure that they avoid experiencing the big one and needing the higher medical costs of dealing with the problem as it arises. In other words, we can all agree that an ounce of prevention is worth a pound of cure. However, let's see if that is actually what we are accomplishing.
Unless you have been hiding under a rock for the past several decades you have heard of statin drugs. Statin drugs are currently the standard of care for treating people with heart disease, despite there being no real evidence that they prevent heart attacks in anyone other than middle aged men who have already had a heart attack. In this very small sample of people, cholesterol screenings are unnecessary because these men are already on statins. For the remainder, let's take a look at what you are buying in to.
Let's say I have a large business with 1000 employees who are not currently on statins and they all sign up for cholesterol screening. The criteria for high cholesterol puts approximately 1 in 3 people in this group, so let's say 333 of your employees are diagnosed with high cholesterol. Most physicians will not prescribe a statin based solely on high cholesterol, so let's assume only 200 of your employees are recommended to take statin drugs. What can we expect to see in terms of results?
If you listen to the way these drugs are marketed, you would realize that statins reduce heart attack risk by 36%, but what does this mean in a way that is pertinent to our discussion? Probably the most clear cut way would be to look at a number that gives you the risk to benefit ratio. In the pharmaceutical world, this is referred to as the number needed to treat (NNT). The NNT is the number of people you would need to treat with the drug in order to prevent 1 person from experiencing the adverse event you are trying to prevent. In other words, in the case of statins, the NNT is the number of people you would need to treat to prevent 1 heart attack. When we look at this number, we get a much clearer picture of what we are getting. The NNT to prevent 1 heart attack varies between 70-250 people depending on the study you look at. When you take in to consideration that this NNT also includes people who have already had a coronary event, the NNT for people that will be undergoing cholesterol screening is closer to 1 in 250. In other words, 249 of the people you are treating with this drug are not benefiting from taking it. Furthermore, you would need to treat all 250 of these people for 5 years with the drug before you would prevent that 1 heart attack.
It is highly likely that every one of the 200 employees you have identified as candidates for statin therapy will receive no benefit from the drug, and you as well as they get to pay for that therapy. In addition, recent research has shown that statin therapy induces diabetes in 1 out of 200 people taking the drugs. So, while you have prevented zero heart attacks you have actually increased your healthcare costs by adding a diabetic to the payroll. By the way, people with Type 2 Diabetes have the same risk of heart attack or dying from heart disease as people who have already had a heart attack. Framed in that context, does that cholesterol screening really sound like something that is going to prove beneficial to your organization or does it seem more like a way to sell you something that is not really going to benefit you at all?
There is, of course, very large healthcare costs associated with someone experiencing a heart attack. You may even hear that spending all of that money treating people with a drug that is not benefiting them in any way may make sense when you look at the cost savings of preventing a heart attack. Ethical considerations aside, this benefit does not exist. High cholesterol isn't even a good indicator of future heart disease. The actual data shows that 50% of the people who die of heart disease have normal cholesterol. In other words, you are financing a screen that has the same likelihood of predicting a heart attack as a coin flip, and investing a large sum of money in it's ability to do that.
Tuesday, December 18, 2012
Stop the Insanity: What’s the deal with Crossfit, P90x and Insanity?
I don’t think I go a week without someone asking me about Crossfit, P90x, or Insanity. My response most of the time is that if it’s something you want to do, do it. Personally, I think all 3 of them are insanity and wouldn’t recommend them to your casual fitness enthusiast or weight loss client, and people often want to know why I think that. Listed below are my primary reasons.
1. For the vast majority of people, they are overkill. You can get the same or better results doing less than half as much total work. Dealing with the general population as much as I do, I can tell you the number of people who have asked me what is the most amount of work they need to do to lose fat is zero. Most, if not all, want to know the quickest, easiest way to lose fat. These 3 methods are none of the above. They require a ton of work and the results you get really aren’t any better than what I’ve seen with my clients who train 3-4 times a week for 30 minutes at a time with tons of rest between sets.
2. Pushing your stress response to the level these people do day in and day out almost always leads to more injuries or illnesses. The last thing someone who is trying to lose weight needs is a reason to quit and both of these reasons are probably the greatest contributors to quitting a fat loss plan.
3. Most people who need to lose fat are coming from sedentary lifestyles. While over time you can certainly prepare them for these types of activities, it would take at least a year just to correct movement dysfunction and learn proper exercise technique, let alone improve their stress response to the point this activity leads to positive adaptation. If you get sore in very specific areas chronically this is almost always due to either over-stressing that tissue or a movement dysfunction.
4. People who are more prone to obesity and Type 2 Diabetes tend to have higher percentages of Type II muscle fibers. These fibers fatigue more easily than Type I fibers and take longer to recover. In order to activate these fibers they cannot be in a fatigued state, they need full recovery. If organized properly you can do higher intensity exercise in a compressed time window while getting full recovery. None of these modalities do that.
5. I agree that intensity is key, but what these programs do isn’t intense by definition. While they are physically draining, intensity is defined by percentage of max force output. If I sprint as fast as I can for 30 seconds, get full recovery, and then sprint as fast as I can for 2 minutes, the second sprint will be more exhausting but the first will be more intense because it will be at a greater speed which requires more force. Also, if I sprint for 30 seconds, get partial recovery, and then try to sprint for 30 seconds again, the second sprint will not be as intense as the first because I will not be able to produce as much force. This is the primary drawback of these types of exercise; partial recovery means partial muscle recruitment. We want total muscle recruitment, not partial.
6. If you have problems regulating your appetite with no exercise, you are going to have a hell of a time regulating it by doing all of this work.
7. Muscle confusion does not exist. Don't get me wrong, I'm not about to compare sports science to heart surgery, but I don't intend on going to a heart surgeon who calls my heart the "Blood pumpy thing". I expect the people I pay to provide a service to know what they are doing and talking about. A muscle cannot be confused any more than a hammer can. Muscles are tools your brain uses to accomplish a task, they don't get confused. If they get used and haven't been used in a while they get sore via inflammation and waste products they are not capable of disposing of. This can both be a positive adaptation or a negative one depending on the magnitude of the soreness.
Don't get me wrong, if your goal is to become a Crossfit athlete you obviously need to join a Crossfit gym. Of the 3, Crossfit is obviously superior because you are getting instruction. I've noticed quite a push in the Crossfit community to develop bridge programs so that sedentary people who want to do crossfit can work their way up to doing it safely. This is a very good move and is causing me to soften on it, I would endorse a gym that does it properly. If you are interested in doing a crossfit program I highly recommend going to one that uses a Functional Movement Screen to drive corrective exercise and has a good bridge program. Realize that most programs that do this are going to be more expensive than ones that don't, but you get what you pay for. It is well worth it to take care of any movement dysfunction up front rather than deal with it after you have learned the movements and need to re-learn them after fixing the problem. As for the other 2 programs...fix your diet, go for walks, and foam roll and strength train 2-3 times per week for 45 minutes at a time. The rest is just overkill.
1. For the vast majority of people, they are overkill. You can get the same or better results doing less than half as much total work. Dealing with the general population as much as I do, I can tell you the number of people who have asked me what is the most amount of work they need to do to lose fat is zero. Most, if not all, want to know the quickest, easiest way to lose fat. These 3 methods are none of the above. They require a ton of work and the results you get really aren’t any better than what I’ve seen with my clients who train 3-4 times a week for 30 minutes at a time with tons of rest between sets.
2. Pushing your stress response to the level these people do day in and day out almost always leads to more injuries or illnesses. The last thing someone who is trying to lose weight needs is a reason to quit and both of these reasons are probably the greatest contributors to quitting a fat loss plan.
3. Most people who need to lose fat are coming from sedentary lifestyles. While over time you can certainly prepare them for these types of activities, it would take at least a year just to correct movement dysfunction and learn proper exercise technique, let alone improve their stress response to the point this activity leads to positive adaptation. If you get sore in very specific areas chronically this is almost always due to either over-stressing that tissue or a movement dysfunction.
4. People who are more prone to obesity and Type 2 Diabetes tend to have higher percentages of Type II muscle fibers. These fibers fatigue more easily than Type I fibers and take longer to recover. In order to activate these fibers they cannot be in a fatigued state, they need full recovery. If organized properly you can do higher intensity exercise in a compressed time window while getting full recovery. None of these modalities do that.
5. I agree that intensity is key, but what these programs do isn’t intense by definition. While they are physically draining, intensity is defined by percentage of max force output. If I sprint as fast as I can for 30 seconds, get full recovery, and then sprint as fast as I can for 2 minutes, the second sprint will be more exhausting but the first will be more intense because it will be at a greater speed which requires more force. Also, if I sprint for 30 seconds, get partial recovery, and then try to sprint for 30 seconds again, the second sprint will not be as intense as the first because I will not be able to produce as much force. This is the primary drawback of these types of exercise; partial recovery means partial muscle recruitment. We want total muscle recruitment, not partial.
6. If you have problems regulating your appetite with no exercise, you are going to have a hell of a time regulating it by doing all of this work.
7. Muscle confusion does not exist. Don't get me wrong, I'm not about to compare sports science to heart surgery, but I don't intend on going to a heart surgeon who calls my heart the "Blood pumpy thing". I expect the people I pay to provide a service to know what they are doing and talking about. A muscle cannot be confused any more than a hammer can. Muscles are tools your brain uses to accomplish a task, they don't get confused. If they get used and haven't been used in a while they get sore via inflammation and waste products they are not capable of disposing of. This can both be a positive adaptation or a negative one depending on the magnitude of the soreness.
Don't get me wrong, if your goal is to become a Crossfit athlete you obviously need to join a Crossfit gym. Of the 3, Crossfit is obviously superior because you are getting instruction. I've noticed quite a push in the Crossfit community to develop bridge programs so that sedentary people who want to do crossfit can work their way up to doing it safely. This is a very good move and is causing me to soften on it, I would endorse a gym that does it properly. If you are interested in doing a crossfit program I highly recommend going to one that uses a Functional Movement Screen to drive corrective exercise and has a good bridge program. Realize that most programs that do this are going to be more expensive than ones that don't, but you get what you pay for. It is well worth it to take care of any movement dysfunction up front rather than deal with it after you have learned the movements and need to re-learn them after fixing the problem. As for the other 2 programs...fix your diet, go for walks, and foam roll and strength train 2-3 times per week for 45 minutes at a time. The rest is just overkill.
Thursday, December 13, 2012
Meal Frequency, metabolism and the mythical stress mode: Why eating 5 times a day is stupid and more than likely counterproductive
Most of you have probably heard the old saying, “You need to eat every 3 hours or your body will enter stress mode and your metabolism will grind to a halt!” You’ve probably heard this from friends, trainer, and maybe even Doctors. When I hear people state this myth it drives me nuts. For one, it shows a complete lack of understanding of the stress response. Secondly, it shows a complete misunderstanding of how the human body works in general. So let’s see where we can shoot this thing down.
To start off, the Thermic Effect of Food (TEF), the mechanism by which you are trying to increase caloric expenditure by eating 5 times a day, accounts for about 10% of calories. That’s right, TEF is related to the calorie load, not the number of times you eat. So, if you eat 2000 calories a day, the TEF will be around 200 calories whether you eat 3 times or 5 times. Now, if you lower calories to 1800, your body will eventually adjust metabolism to that rate and you will stop losing weight. However, if you increase consumption to 2200 calories, your body will actually increase metabolism. The point here is that there is no stress mode, the body just adapts to the number of calories you put in to it by increasing and decreasing efficiency as well as increasing fidgeting and non-exercise related energy consumption. This is fairly common knowledge outside of the Muscle and Fitness crowd.
Now, does your metabolism grind to a halt when you fail to eat every 3 hours? Given that studies of fasting have actually shown INCREASES in resting energy expenditure during fasts of 84 hours (1), I’m going to go out on a limb and say that skipping your mid morning snack should leave your metabolism pretty well intact. Oddly enough, given that the Autonomic Nervous System (ANS) partitions resources based on eating and physical activity, eating 5 times a day may be a bad idea for energy levels. Your ANS controls most of the automatic processes in your body. You know, things like heart rate, blood pressure, digestion, breathing rate, etc. Most people have heard of the fight or flight, or stress, response. The fight or flight response is controlled by your ANS. You don’t need to know the specifics of it, but your ANS is a continuum from rest and digest to fight or flight and is handled by 2 branches of the ANS, the Sympathetic and Parasympathetic Nervous Systems.
When you encounter a stressful situation, your ANS increases blood flow to your muscles, floods your bloodstream with stress hormones, and increases heart rate, blood pressure, and breathing rate so that you can either fight what is coming at you, or flee and live to fight another day. This is handled by an increase in Sympathetic Nervous System activity. When you are resting or eating, your ANS directs blood flow to the organs of digestion while also lowering heart rate, blood pressure, and breathing rate. This is accomplished by an increase in Parasympathetic Nervous System activity.
This is why irritable bowel syndrome is so tightly linked to stress. If you are highly stressed, blood is shunted away from your organs of digestion and towards your muscles, preventing you from digesting your food properly. In the same way, if you are constantly digesting the food you’ve eaten, blood is shunted away from your muscles and toward your organs of digestion. This is why most people tend to feel sluggish after they eat. Optimally your body should switch between the two easily so that you have energy and you can digest your food properly. As such, it’s probably a good idea to give your organs of digestion a rest every now and again by eating 3 times a day or less. In fact, the above referenced study showed the increase in caloric expenditure during fasting was due to an increase in norepinepherine, one of the stress hormones secreted in response to fight or flight.
According to most accounts, we evolved by eating a very small meal in the morning followed by a large meal at night with no lunch in between. To say eating 5 times a day is necessary for fat loss shows a thorough misunderstanding of rudimentary human physiology.
References
1. Zauner, C. et al. Resting energy expenditure in short-term starvation is increased as a result of an increase in serum norepinephrine. Am J Clin Nutr. 2000 Jun; 71(6): 1511-5.
To start off, the Thermic Effect of Food (TEF), the mechanism by which you are trying to increase caloric expenditure by eating 5 times a day, accounts for about 10% of calories. That’s right, TEF is related to the calorie load, not the number of times you eat. So, if you eat 2000 calories a day, the TEF will be around 200 calories whether you eat 3 times or 5 times. Now, if you lower calories to 1800, your body will eventually adjust metabolism to that rate and you will stop losing weight. However, if you increase consumption to 2200 calories, your body will actually increase metabolism. The point here is that there is no stress mode, the body just adapts to the number of calories you put in to it by increasing and decreasing efficiency as well as increasing fidgeting and non-exercise related energy consumption. This is fairly common knowledge outside of the Muscle and Fitness crowd.
Now, does your metabolism grind to a halt when you fail to eat every 3 hours? Given that studies of fasting have actually shown INCREASES in resting energy expenditure during fasts of 84 hours (1), I’m going to go out on a limb and say that skipping your mid morning snack should leave your metabolism pretty well intact. Oddly enough, given that the Autonomic Nervous System (ANS) partitions resources based on eating and physical activity, eating 5 times a day may be a bad idea for energy levels. Your ANS controls most of the automatic processes in your body. You know, things like heart rate, blood pressure, digestion, breathing rate, etc. Most people have heard of the fight or flight, or stress, response. The fight or flight response is controlled by your ANS. You don’t need to know the specifics of it, but your ANS is a continuum from rest and digest to fight or flight and is handled by 2 branches of the ANS, the Sympathetic and Parasympathetic Nervous Systems.
When you encounter a stressful situation, your ANS increases blood flow to your muscles, floods your bloodstream with stress hormones, and increases heart rate, blood pressure, and breathing rate so that you can either fight what is coming at you, or flee and live to fight another day. This is handled by an increase in Sympathetic Nervous System activity. When you are resting or eating, your ANS directs blood flow to the organs of digestion while also lowering heart rate, blood pressure, and breathing rate. This is accomplished by an increase in Parasympathetic Nervous System activity.
This is why irritable bowel syndrome is so tightly linked to stress. If you are highly stressed, blood is shunted away from your organs of digestion and towards your muscles, preventing you from digesting your food properly. In the same way, if you are constantly digesting the food you’ve eaten, blood is shunted away from your muscles and toward your organs of digestion. This is why most people tend to feel sluggish after they eat. Optimally your body should switch between the two easily so that you have energy and you can digest your food properly. As such, it’s probably a good idea to give your organs of digestion a rest every now and again by eating 3 times a day or less. In fact, the above referenced study showed the increase in caloric expenditure during fasting was due to an increase in norepinepherine, one of the stress hormones secreted in response to fight or flight.
According to most accounts, we evolved by eating a very small meal in the morning followed by a large meal at night with no lunch in between. To say eating 5 times a day is necessary for fat loss shows a thorough misunderstanding of rudimentary human physiology.
References
1. Zauner, C. et al. Resting energy expenditure in short-term starvation is increased as a result of an increase in serum norepinephrine. Am J Clin Nutr. 2000 Jun; 71(6): 1511-5.
Saturday, December 1, 2012
Myths, Metabolism, & Appetite Part 1
A year ago I decided to start writing up a little piece on what I thought was the stumbling block for most people with regard to losing weight. That little piece ended up being 25 pages long so I decided I would break it up and post it as a blog. The entire piece is fully referenced and I will post the references at the end of each part.
Myths, Metabolism, and Appetite
Humans have been evolving for the better part of 2 million
years. During the vast majority of this
time, approximately 1.97 million years, we’ve run, we’ve jumped, we’ve swam,
we’ve paddled, we’ve climbed, we’ve crawled, we’ve thrived. The adaptability our genome has given us has
allowed us to survive in every environment we’ve encountered up until now. Recently, technology has allowed our environment
to evolve much more quickly than our genes allow us, leading to an epidemic of
obesity and Type 2 diabetes. This
epidemic costs the country nearly $300 billion per year.
It’s not terribly difficult to identify the aspects of our
environment that have led us to this epidemic. A clever primate that has flourished in environments
where food is scarce and physical activity is a requirement to find food is not
suited to an environment where physical activity is optional and food can be
attained quite easily. This primate has
been naturally selected over the course of millions of years to eat when food
is available and to exert as little energy as possible to get that food. Now that the environment allows this very
thing, we are getting the product of that gene/environment interaction and it’s
not pretty.
All is not lost, however.
There is quite a bit one can do to turn this predicament around, we just
need to be that clever primate and look deep within science for solutions. Unfortunately, our current course is both not
working and, when you look at what the science shows, actually driving us
deeper in to the hole that we’ve dug. In
part 1 of this series we will discuss how the conventional wisdom being passed
off to you by your doctors, trainers, and the popular press is all wrong. In part 2 of this series, we will discuss how
your metabolism works and how this runs counter to what they tell you. In part 3 we will discuss diet and the
science behind why we continually fail.
PART 1
When you go to your doctor and present as obese or
overweight, their standard of care is to tell you to eat less calories and burn
more. For most people this does not
work, and in a good chunk of the people that it does it only works in the
short-term, eventually leading back to the same weight or even worse, more
weight gain later down the line. Much of
this, as well as nearly all processes in the body, is driven by hormones. Hormones are chemicals that the body uses to
communicate between systems. We can use
what we know about hormones to control many things related to weight such as
appetite, energy levels, stress levels, and fuel selection. Telling someone to count calories and burn
more completely ignores these hormonal shortcuts, making the task of weight
reduction and maintenance much more difficult.
Of the advice that you are given, there are 4 key notions that mislead
people down the wrong path: A calorie is a calorie, burn as many calories as
you can, carbohydrate is the body’s preferred fuel source, and whole grains are
good for you,.
A Calorie is a Calorie
Before we go on, it is important to say that, of course, a
calorie is a calorie, what else would it be?
The problem with this notion is that it is irrelevant to the
discussion. For one, we can all agree
that ammunition is ammunition, but a BB pellet and a bazooka shell are not the
same thing. They may share a few common
traits, but for the most part we can all agree that they probably have more
differences than similarities. In much
the same way, the calories you consume are quite different from one another based
on their source.
Most people look at their food as energy and that energy is
measured in calories. What most people
don’t realize, however, is that we do not even use our food for energy, we use
a substrate called ATP (Adenine Triphosphate).
All of our cells use ATP for energy, and ATP is stored within our cells
and recharged with the food we eat. As
such, there is no calorie receptor on your cells, and your cells do not look at
what you consume as calories, it views it as raw materials. Once the food you eat is broken down in to
amino acids from protein, glucose from carbohydrate, and fatty acids from fat,
it can enter your cells. The kicker here
is that not all of what you eat is used for energy. All of it can
be used as energy, but your body uses amino acids to build structures and
enzymes to catalyze reactions and fats to build hormones and repair cell walls
on top of what they provide for energy.
Certainly these proteins and fats contained energy when you consumed
them, but if you are not using them for energy purposes, do we really concern
ourselves with the calories they contain?
But wait, it gets even more interesting.
A nutrient is considered essential when the body needs it but
cannot manufacture it from other nutrients.
Therefore, you need to eat this nutrient directly in order to remain
alive. There are essential amino acids,
essential fatty acids, but there are no essential carbohydrates. But how can this be? It’s actually quite simple, your body needs
glucose which carbohydrates provide, but so can amino acids and a portion of
the fat molecule called glycerol. The
conversion of non-carbohydrate to glucose is called gluconeogensis and is
performed by the liver under the direction of hormones. In fact, for 1.97 million years,
gluconeogenesis probably provided the bulk of our glucose needs with vegetables
and fruit kicking in as well. Obviously
since agriculture became big this has changed, and that is one of the primary
drivers of our current obesity epidemic.
With the way our bodies work, this could eventually lead to the human
genome shedding the genes necessary for gluconeogensis, which would be a bad
scene if carbohydrates ever become scarce again.
As mentioned above, carbohydrates are broken down in to
glucose and fats are broken down in to fatty acids so they can enter our cells
for regeneration of ATP. Amino acids
provide energy as well, but only after being converted in to glucose
first. But what are the differences
between glucose and fatty acids with regard to their energy qualities? The first and most striking difference is
that glucose recharges ATP at a much faster rate than fatty acids do.
If you are looking to sprint short distances or perform
explosive movements such as jumping, fatty acids cannot recharge ATP stores
fast enough so you fatigue once your ATP stores are used up. To perform this type of activity for a
considerable amount of time, the bulk of ATP regeneration will come from the
breakdown of glucose with fatty acids providing a small amount. Once you stop performing the explosive action
or decide to do something more along the lines of long distance running or
walking, fatty acids will kick in the bulk of ATP regeneration.
While fatty acids are much slower at recharging ATP, they
recharge a lot more of it. The breakdown
of 1 glucose molecule will yield 38 ATP while the breakdown of a fatty acid
molecule will yield 128 ATP, which is quite a difference. So, while a calorie may be a calorie, are
glucose and fatty acids the same? The
reactions by which they recharge ATP are completely different, with glucose
being metabolized anaerobically (Without oxygen) within the cytoplasm of the
cell and fatty acids being oxidized aerobically (With oxygen) by the
mitochondria. Given the qualities of
each, they seem suited for different goals.
Specifically, glucose is a more
appropriate fuel source when you need bursts of energy while fatty acids are a
more appropriate fuel source when you need a lot of energy but are in no hurry
to get it.
Making the “A calorie is a calorie” approach even more
frustrating and weak is the fact that as you cut calories your body adapts by
burning less calories to accomplish the same tasks. This is true and happens even with no loss of
muscle mass(1, 2, 3). So while it is still true that a calorie is a calorie,
your body changes the rules of the game by burning fewer calories to do the
same thing. Now you need to either cut
more calories out of your diet or burn more.
By the time you get anywhere near your goal weight you’ll be eating 500
calories a day and exercising 10 hours a week.
The current theory on why this happens is that your body
resists burning fat because it is holding on to energy in case of famine. This is a nice theory and all, but if you
look deeper it is certainly not the case.
Why? Because when you increase
your caloric consumption your body adjusts by burning MORE calories, and it can
do this to the same extent as lowering metabolism when you lower calorie
intake. If the human machine is so
concerned with conserving calories, why do the rules change during
overconsumption of calories?
Obviously this is an adaptation to the environment and not
some uni-directional stress mode that rains on your weight loss parade. Lowering your metabolism is basically your
body’s way of becoming more efficient, burning a smaller amount of energy to
accomplish the same tasks. Put another
way, instead of being able to drive 400 miles to the gallon, now your car can
go 500 miles to the gallon. This is a
positive thing and a preferred state that most people looking to lose weight do
not want to hear because they are preoccupied with counting calories. When you look at the amount of calories you
need to either cut out of your diet or burn just to lose 1 pound of fat you’ll
probably faint.
Burn as many calories
as you can
How many calories do you need to burn to lose a pound of
fat? I’m sure all of you have been given
an answer by either your trainer or doctor, but I can assure you that the
number you were given wasn’t accurate.
Most people were never fans of word problems as kids, and they typically
carry that distaste in to adulthood. If
you look at the questioned I posed, I asked how many calories you need to burn
to lose 1 pound of fat. Your answer was
probably 3500, which is basically the number of calories in a pound of
fat. The problem with this is that it’s
not the question I asked. You see, while
there are indeed 3500 calories in a pound of fat, you are never burning 100% of
your calories from fat.
The largest percentage of calories from fat your body will
use for fuelvis 60%. I will not bore you
with the math, but this puts the MINIMUM number of calories you need to
burn to lose a pound of fat at 5833.
Just to give you an idea, a 160lbs male would need to run at 8mph for 7
hours to burn a pound of fat at that rate, a 7.5 minute mile. Mucking up your long distance running plans
even further, your body burns the highest percentage of fat at rest and it
drops as the intensity of your exercise increases. So, as you pick up the pace, you are burning
a smaller percentage from fat, increasing the number of calories you need to
burn to drop a pound of fat if you are merely concerning yourself with calories
in vs calories out. I would love to tell
you this is the only problem with long distance running or chronic cardio, but
it’s not. Actually, that’s a lie, I hate
long distance running and the fact that it is unnecessary is why I don’t do
it. You see, there has been a
significant amount of research in this area for quite some time and all of it
has shown that high intensity training outperforms long distance, low intensity
training for fat loss as well as markers of carbohydrate and fat metabolism(4,
5, 6, 7)). The most telling study took
place in 1994 by Tremblay, et al. This
study showed that when matched calorie for calorie, high intensity interval
training led to a 9x greater reduction in body fat than did running at a
constant pace (7). How can that be, a
calories is a calorie, right? While that
is true, your body is not merely a machine that burns fuel, it’s quite a bit
more complicated than that. In Part 2,
we will go over the human machine in more detail.
Carbohydrates are the body’s preferred fuel source
This one is actually one of the easier myths to refute
because the science it is based on is foolish.
The reason given for carbohydrates being the body’s preferred fuel
source is that they are metabolized first.
The problem with this is they aren’t.
If you put fats, proteins and carbohydrates in to the body the
carbohydrates will convert to glucose which will be used first. If you add alcohol in to the mix alcohol is
actually metabolized first, and I am going to go out on a limb here and say
your doctor is not going to say alcohol is your body’s preferred fuel source.
If you recall from the calorie is a calorie section, alcohol
aside, the energy sources from food actually have very specific attributes that
lend themselves better to particular needs.
Recall that glucose, the primary substrate from carbohydrate, provides a
moderate amount of energy quickly while fatty acids from fat provide a lot of
energy but at a slower rate. I suppose a
good metaphor is that glucose is jet fuel while fatty acids are more like
diesel fuel. For the most part, the
obesity epidemic is primarily driven by people eating a jet fuel diet while
living a diesel fuel lifestyle. Putting
jet fuel in a diesel engine would cause the engine to run hot and blow out, in
humans it tends to cause a hormonal response that leads to fat gain and,
eventually, obesity. This is because the
human machine has a few things that separate it from the engine. However, the running hot analogy does hold
true for the human body as that is precisely what happens in Type 2 Diabetes.
Another case against carbohydrates being the preferred fuel
source is our limited ability to store it.
A well trained athlete can store approximately 500g of glycogen (The
storage form of glucose), or 2000 calories.
A 160lbs male with 15% body fat has 9,333g of stored energy as fat,
which accounts for 84,000 calories. For
glucose containing carbohydrate being the body’s preferred fuel source, we sure
are lousy at storing it. Our glycogen
stores are enough to power the body for about a day whereas you could run on
your fat stores for weeks. Add to this
the fact that excess carbohydrate will convert to fat while excess fat will
only be stored as fat, and the grounds that “Carbohydrate is the body’s
preferred fuel source” is on is shaky, at best.
Whole grains are good for you
Who on the planet has not heard the term heart-healthy whole
grains? Few actually know this, but there
are quite a few reasons why whole grains are not good for you. Since we are dealing with fat loss, we will
not go over the fact that they bind nutrients and possibly prevent you from
absorbing them(8, 9, 10, 11). We will
also skip over the fact that grains contain storage proteins such as gluten
that are a problem for a lot of people. For
the purposes of this article we will only concern ourselves with the flawed
research used to manipulate you in to thinking whole grains are healthy as well
as their impact on energy.
Just to knock the research portion out of the park right
away, 100% of the research showing whole grains to be healthy doesn’t actually
show that. There have been 3 studies
that I am aware of that directly compare whole grains to not eating grains at
all, and the no grain group in each study had healthier outcomes (12, 13, 14). In addition, an older study showed complete
remission of Type 2 Diabetes in a group of Australian aboriginals that reverted
back to their traditional, grain-free hunter/gatherer diet (15). All of the studies that show whole grains to
be “healthy” have compared them to refined grains, which we know are not
healthy. So do those studies really show
whole grains to be healthy, or do they just show them to be healthier than
refined grains? Put another way, if I
ran a study that showed crack to be healthier than heroin, would that study
show crack to be healthy? I rest my case
on that one.
Outside of the aforementioned issue with nutrient binding
which is certainly not a trivial issue, whole grains are a large source of
carbohydrate. Since these carbohydrates
will eventually be broken down in to glucose, they will provide a quick source
of energy. This is actually not a bad thing
if you are someone who needs quick access to energy like a day laborer or an
athlete, but if you are sitting on your rump all day long you are certainly not
in need of quick access to energy.
Your doctor may have explained to you that the glucose from
whole grains enters your bloodstream more slowly than, say, table sugar. What he or she may have failed to mention is
that 2 slices of whole grain bread will eventually dump the equivalent of 5
teaspoons of table sugar in to your bloodstream. Add in a serving of pretzels and you are
dealing with about 10 teaspoons of table sugar.
Just for comparison’s sake, your entire blood volume holds just a hair
under 1 teaspoon of glucose at a time.
No matter how you swing it, that is a ton of fast acting energy that a
sedentary person does not need so they are more than likely going to store it
with the help of a hormone called insulin.
Humans are
biologically driven to seek food and expend as little energy as possible to get
it, and this is driven by hormones.
Thanks to evolution via natural selection, a majority of us are
engineered perfectly to eat as much as possible when the opportunity presents
itself because it has been scarce for the vast majority of time. Insulin allows us to store fast acting energy
for a time when we will need it, a fact most people know. From this point of view, we no longer need
insulin for energy storage since we are in an environment where food is
plentiful and there is no need to expend energy to get it. However, when you look at it from a blood
glucose point of view, insulin is actually trying to pull glucose out of your
bloodstream as fast as it can because high levels of blood glucose are very
damaging to your blood vessels and organs.
Our hormones make us ill-suited to our current environment.
In Part 2 we will examine how our metabolism works and things that
we should be doing to keep it working properly.
References
1.
Gornall J, Villani, RG. Short-term changes in
body composition and metabolism with severe dieting and resistance exercise. Int J Sport Nutr 1996; 6:
285–294.
2. Johansen,
DL, et al. Metabolic
Slowing with Massive Weight Loss despite Preservation of Fat-Free Mass. The Journal of Clinical Endocrinology
& Metabolism April 24, 2012 jc.2012-1444.
3.
Thompson JL, Manore MM, Thomas JR. Effects of
diet and diet-plus-exercise programs on resting metabolic rate: a
meta-analysis. Int J Sport Nutr 1996; 6: 41–61.
4.
Boutcher SH. 2011. High-intensity intermittent exercise and fat
loss. J Obes.
2011:868305. Epub 2010 Nov 24.
5.
Perry CG,
Heigenhauser GJ, Bonen A, Spriet LL. 2008 High-intensity
aerobic interval training increases fat and carbohydrate metabolic capacities
in human skeletal muscle. Appl
Physiol Nutr Metab. Dec; 33(6):1112-23.
6.
Talanian JL,
Galloway SD, Heigenhauser GJ, Bonen A, Spriet LL. Two
weeks of high-intensity aerobic interval training increases the capacity for
fat oxidation during exercise in women. J
Appl Physiol. April, 2007;
102(4):1439-47.
7.
Tremblay
A, Simoneau J-A, Bouchard C. Impact of exercise intensity on body fatness and
skeletal muscle metabolism. Metabolism. 1994;,43(7):814–818.
8.
Bohn T, et al. 2004. Phytic
acid added to white-wheat bread inhibits fractional apparent magnesium
absorption in humans. American Journal of Clinical Nutrition. 2004
79:418-23.
9.
Navert B and
Sandstrom B. Reduction of the phytate content of bran by leavening in bread and
its effect on zinc absorption in man. British
Journal of Nutrition 1985 53:47-53.
10.
Singh M and
Krikorian D. Inhibition of trypsin activity in vitro by phytate. Journal of Agricultural and Food Chemistry
1982. 30(4):799-800.
11.
Tannenbaum and
others. Vitamins and Minerals, in Food Chemistry, 2nd edition. OR Fennema, ed.
Marcel Dekker, Inc. New York, 1985, p 445.
12.
Frassetto LA, Schloetter M, Mietus-Synder M,
Morris RC, Jr., Sebastian A: Metabolic and physiologic improvements from
consuming a paleolithic, hunter-gatherer type diet. Eur J Clin Nutr 2009.
13.
Jonsson T, Granfeldt Y, Ahren B, Branell UC,
Palsson G, Hansson A, Soderstrom M, Lindeberg S: Beneficial effects of a Paleolithic diet on cardiovascular risk
factors in type 2 diabetes: a randomized cross-over pilot study. Cardiovasc Diabetol 2009, 8:35.
14.
Lindeberg S, Jonsson T, Granfeldt Y,
Borgstrand E, Soffman J, Sjostrom K, Ahren B: A Palaeolithic diet improves
glucose tolerance more than a Mediterranean-like diet in individuals with
ischaemic heart disease. Diabetologia
2007, 50(9):1795-1807
15.
O’Dea K: Marked improvement in carbohydrate
and lipid metabolism in diabetic Australian aborigines after temporary
reversion to traditional lifestyle. Diabetes
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