Human Variability and Diet

It’s a simple conclusion to make, that there’s one perfect diet for everyone. And while I tend to think some foods are generally good and some are generally bad, the reality is that there isn’t one way to eat and one person’s ideal diet might not be beneficial to someone else. We don’t all react to food the same way it’s important we understand this. There are many ways we differ when it comes to the ways our body handles food. For example…

1. Enzymes of Digestion: Amylase in an enzyme which allows us to digest starch and utilize foods like potatoes (“boil em’, mash em’ stick em’ in a stew”) as sources of nutrition. Amylase production in the body is directly correlated with the number of copies of the AMY1 gene a person has and is influenced by several other factors as well. This means that the ability to digest starchy foods differs notably from person to person and is heavily decided by genetic factors. Some people might find their health suffering if they eat a diet high in starchy foods, while other might thrive. This is one example, but we use enzymes every time eat food–we have enzymes for digesting fat, protein, and carbohydrates and, as with amylase, everyone’s production of these enzymes isn’t always the same.

2. Apolipoproteins*: Imagine you just ate a plate of bacon and eggs, a block of cheese, or some beef brain in coconut milk (trust me, it tastes better than it sounds). When we eat such foods, the fat and cholesterol contained in them is digested in our bodies and sent via our blood streams to the places where they’re needed. But because such compounds are insoluble in water, a compound called VLDL is needed to transport the fat and cholesterol around our circulatory system like a chauffeur. This is where apolipoproteins (or APO’s) come in; APO’s are proteins that allow for the formation of important lipoproteins (such as VLDL). One specific type, APOE, allows our cells to use to the fat we eat. APOE comes in three forms and varies from person to person much like blood type. The forms are APOE2, APOE3, and APOE4. People with a copy of either E2 and E4 are at higher risk for heart disease, compared with type e3 (the most common type). Those with types e2 or e4 appear less able to process dietary fat in their blood stream, which can lead to atheroscerlosis. To use an example, a majority of indigenous people from New Guinea have type e4 yet have low rates of heart disease because they subsist on a low fat diet of starchy root vegetables, sugar cane, and occasional lean meats. Evidence suggests people with e4 are quite susceptible to heart disease when eating a lot of fat and benefit from such a diet that reduces it. Personally, I think a high fat diet can be healthy, but some people may simply receive the most benefit from going low fat.

3. Food Intolerance: Everyone once in a while we meet someone with such a severe allergy to nuts that the mere smell of a walnut causes their throat to close up and their face to swell up like a hot air balloon. While most nuts can absolutely be a good addition to a healthy eating plan, this would clearly not be the case for someone with a nut allergy. But such an intense allergy is an extreme example, so lets look at something that’s a bit more common: food intolerance. My good friend Wikipedia defines food intolerance as “a negative reaction, often delayed, to a food, beverage, food additive, or compound found in foods that produces symptoms in one or more body organs and systems”. Someone with lactose intolerance might drink a glass of milk and find out that the phrase “negative reaction” can mean “being gassy as hell”. This is only one example of food intolerance, so here’s another one: fructose malabsorption. Fructose malabsorption is fairly common and can cause symptoms of stomach pain, bloating, constipation, and diarrhea when excess fructose is consumed. Fructose is notably found in fruit, so it might be advisable that a person with fructose malabsorption avoid eating a lot of fruit. This clearly runs contrary to typical health advice to eat a “shit ton of fruit” (I think that’s an exact quote from the AHA). I don’t disagree that fruit is healthy and everyone should probably be eating fruit, but some people should clearly exercise some restraint. Fructose malabsorption and lactose intolerance are two common examples of food intolerance but it barely scratches the surface of what foods a person can react negatively to. Although we can have ideas about what foods are “healthy”, some people simply defy this and should avoid certain foods.

The point I was trying to make is that there is no “one size fits all” diet. Whatever foods make up a person’s diet, if that person claims to be and seems to be thriving (and not eating bastardized, industrial versions of said foods), I tend to believe them. It’s about finding what works and what doesn’t. Self-experimentation can be a valuable tool. When I eliminated wheat from my diet, a wide range of gastronomical ailments practically disappeared and I had more energy. But this was only my experience, it’s up to you to do your own research into what works for your body. Just steer clear of refined, processed, industrial non-food. Instead, choose real food close to nature. Figure out what makes you feel your best and eat that way.

*-Much of my information on apolipoproteins comes from a book called Genome: The Autobiography of a Species in 23 Chapters. It’s a great read and I recommend it to anyone interested in learning about human genetics.


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