When most people hear the term "the walking dead", it conjures up the image of zombies running amuck in a post-apocalyptic world. Legions of the brain dead undead doing the Frankenstein and looking to devour the brains of any live person within their grasp. However, many of us know a different type of walking dead, one whose transition is far slower. It may begin in their late 40s or early 50s as they lose track of where they put things or misremember things that have happened in their past. Slowly but surely the zombification progresses until they no longer remember friends and family, eventually losing the ability to express themselves, understand a conversation, or even respond to the environment. The walking dead I am referring to are people going through dementia and/or Alzheimer's disease.
While there is an enormous emotional price to having a loved one with dementia or Alzhemier's disease that can't be quantified, there is also an enormous price tag to go along with it. In 2013 alone, the direct costs of Alzheimer's disease in the US was $203 billion and is expected to balloon up to $1.2 trillion per year by 2050(1). Not included in this number is the unpaid care that family give to people with Alzheimer's disease, estimated to be $216 billion in 2012.
Many people associate dementia and Alzheimer's as being a normal part of aging. While it is true that Alzheimer's progresses with age, it is certainly not a normal part of aging. With Alzheimer's comes structural changes within the brain, an accumulation of beta amyloid plaques and tangles in a protein called tau that interfere with normal brain function. While these plaques and tangles tend to accumulate in everyone as they age, they accumulate to a far greater extent and in a consistent pattern in people with Alzheimer's disease. Furthermore, quite a bit of research has recently pointed to dementia and Alzheimer's disease as autoimmune diseases. This is evidenced by high levels of cells of the immune system called immunoglobulins(2) and other immune system proteins(3) in the brains of people with varying degrees of dementia, including Alzheimer's disease.
The brain is meant to be a sanctuary from immune activity. The blood brain barrier prevents large particles such as bacteria and antibodies from entering the brain and causing problems. Within the blood brain barrier are proteins called tight junctions that seal off the area and help regulate what can or cannot enter the brain. These tight junctions are dissolved by a protein called zonulin(4, 5). What makes this interesting is the fact that both the lungs and the gut also contain tight junctions, and zonulin has the same effect on the tight junctions in those tissues as well. Intestinal permeability occurs when the tight junctions between cells of the intestine fail to prevent large particles from entering the blodstream. It is believed that this is due to zonulin dissolving the tight junction. Making this an even more intriguing relationship is that intestinal permeability appears to be a necessary component of many, if not most, autoimmune diseases(6, 7).
A recent study comparing the postmortem brains of people with Alzheimer's disease to healthy controls found the presence of an oral bacteria known to cause periodontal disease in 4 out of the 10 brains of people with Alzheimer's disease and none in the controls(8). Many look at this as evidence of there being a link between periodontal disease and Alzheimer's disease, but if it were a direct link all of the samples of brain tissue from people with Alzheimer's would have it. However, in a person with a properly working blood brain barrier, this bacteria should not have access to the brain. This study supports the notion that a poorly functioning blood brain barrier is a significant causative factor in Alzheimer's disease. Could this be the result of zonulin dissolving the tight junctions? We don't know for sure, but there is ample reason to suggest so.
Many people are aware of gluten. All you have to do is walk in to any grocery store and you get bombarded with gluten free this, or gluten free that. While many people go gluten free, many have no idea what gluten is or why they are going gluten free. One of the few groups who do know what gluten is are people with celiac disease. Celiac disease is an autoimmune disorder that affects the intestinal lining. When someone with celiac disease eats gluten or any other grain containing gliadin, damage occurs to their intestinal tract that causes pain and discomfort as well as malabsorption of nutrients. This can eventually put them in a malnourished state. Part of this response is due to the release of zonulin, which occurs when gliadin interacts with the intestinal wall and causes intestinal permeability..
However, in a study looking at the intestinal tissue of people with celiac disease and people without celiac disease, zonulin appears to be released in both scenarios, albeit for 30 times longer in people with celiac disease(9). It appears that gut bacteria may have a big role in this as people with celiac disease have different gut bacteria than healthy people, and gut bacteria heal the tight junctions when they ferment soluble fiber and resistant starch in to butyric acid. It is important to point out that these tissue samples were removed from people and then treated with zonulin, and were not tested in a living person.
So we have a potential mechanism for Alzheimer's disease where gluten is ingested and interacts with the cells of the intestine causing zonulin release that dissolves the tight junctions there as well as in the blood brain barrier. This allows particles, including inflammatory ones, that shouldn't be in the brain to cross the blood brain barrier and react with structures within the brain. This doesn't necessarily mean that anyone who experiences intestinal permeability will experience Alzheimer's disease, there are far too many factors to take in to consideration. However, I tend to think that people can realize that the blood brain barrier is there for a reason. Compromising the blood brain barrier is a bad idea whether you are genetically prone to Alzheimer's disease or not. One of the problems is you wouldn't know if this was happening or not, there are no pain receptors in the brain so inflammation doesn't typically show up as pain, it shows up slowly as brain dysfunction over time. Furthermore, inflammation compromises the blood brain barrier further.
So what role does American agricultural policy play in this mess? It's very simple. Every year the federal government gives subsidies to "farmers" to grow wheat. I put farmers in quotation marks because most of the people receiving these subsidies are not family farmers, they are large corporations that do farming. The USDA, a lobbying group for these corporate farmers, lobbies the federal government to get these subsidies and then distributes the money to farmers. From 1995-2012, farm subsidies for wheat alone were $35.5 billion(10). This is the reason it's cheaper to buy bread than it is to buy fruits and vegetables. Most people assume it's because bread is cheaper to grow, but this is only the case if you are subsidizing it's production.
This seems innocent enough, the purpose of most lobbying groups is to lobby the federal government for the organizations they represent. However, the USDA has another role. Many of you are familiar with the Food Pyramid/MyPlate which dictates which foods you should be eating regularly. The problem is that it's not written by a bunch of doctors commissioned to make Americans healthy. It's written by the USDA, a trade group that helps determine which foods can be easily produced and which ones are most profitable. There was no grand experiment decades ago to help determine the foods that are fit for human consumption and then translated in to a set of ground rules for healthy human eating. The USDA stated what could be made and that became the contents of the Food Pyramid, which most people assume are a set of healthy eating rules. To make maters worse, physicians and nutritionists in the healthcare industry push these rules as if that is exactly what they are.
The problem doesn't end there. As many of you know, much of the nutritional research to date has shown grains, especially wheat, to be a healthy food option that leads to positive health outcomes. However, this research is tainted because they essentially told everyone that grains are a healthy food choice without having the research to back it up. If you tell a group of people that a certain food product is healthy, which people do you think are going to consume that product? Typically, you are going to get people who are interested in being healthy. This means they are interested in doing other healthy things like exercising, not smoking, getting quality sleep, and a host of other healthy lifestyle choices. This throws off the research because on one side you have people who are doing everything right and on the other side you have people doing everything wrong. If the side doing everything right is told that they should be eating grains and they do, it's not scientifically valid to compare the 2 groups.
As you can see, there is much to be frustrated about with the way we determine which foods people should eat. When you make foods cheap, you make them more appealing to people and increase the likelihood that people will consume them. This drives people to make the wrong choices, especially poor people who are on a limited income. What people don't realize is that these foods really aren't cheap when you factor in the tax dollars needed to subsidize them and the potential health ramifications they can cause before they are adequately tested. Grains, especially wheat, may be costing us money up front in the form of tax dollars as well as on the back end with the emotional and financial costs associated with Alzheimer's disease. Many people will read this statement and say that there is no research that supports this notion. However, just because there is no research directly linking the consumption of grains with Alzheimer's disease doesn't mean it's not true. At one time the "research" pointed to the Earth being flat, that doesn't mean it was flat until the research showed it to be round.