I structure my nutritional philosophy around the notion of the Paleolithic Principle. The principle is that the human animal has been around and eating a relatively consistent diet for a couple of million years with Homo Sapiens being around for almost 100k years. It was only really with the introduction of the neolithic age that technology brought new foodstuffs to consume such as dairy, grains, and the other modern cultivars of plants that we eat. The paleolithic principle states that we have not fully adapted to these new types of foods and hence they may be harmful to our health, on a case by case basis.
These new sources of food were introduced roughly 5000 - 7000 years ago, which is perhaps some 300 generations worth of time. Humans, being long-lived, evolve quite slowly. Humans, being highly social sentient apex predators, also don't necessarily experience the same degree of natural selection as other species. The question is then, just how well adapted are we to these neolithic food groups?
We know for a fact that food tolerances have an ethnic bias. We know that the closer one's ancestors hailed from Mesopotamia the less likely they are to be intolerant to wheat gluten. Similarly, Asians are far more likely to be lactose intolerant than Europeans. Thus, clearly, only certain segments of the human population have adjusted to each particular Neolithic foodstuff. These are established facts, and they provide a basis for the paleo principle as a reasonable hypothesis.
If one has an ethnic background that strongly identifies with a particular ethnic diet then you might be best off following it since you're probably selected for it. This doesn't always work well however, especially in the immigrant nations such as the USA and Canada, where there has been a great deal of mixing in ethnic groups. Personally, I'm a mix of Polish-Romanian jew, Italian, French, Norwegian, Scottish, Austrian, and English, with a few other nationalities thrown in for fun. If I were to follow an ethnic diet, which of the ten or so should I pick? Almost all of the neolithic food groups give me some trouble. Perhaps I'm simply lacking in intestinal fortitude.
The largest quantity of pharmaceuticals that one ingests by far is in the form of foodstuffs. Plants especially contain an enormous number chemical compounds, not all of which are broken down before they cross the gut-blood barrier. For whatever reason, the gut-blood barrier and the associated bacterial biofilm has broken down more commonly in modern man.
Of course, even foodstuffs that we have been (slowly) adapting to over 5000 - 7000 years have changed a great deal. For example, the heavy fertilization of dwarf wheat strains has resulted in higher protein yields but that protein predominantly comes in the form of increased gluten content. So when people scratch their heads about the increased incidence of celiac and other gluten related autoimmune disorders, it may just be that the wheat is changing rather than the people, n'est-ce pas? Similarly ever compared a wild strawberry to a super-fertilized all-season Californian monstrosity? We have started supplementing our diet with artificial food additives, such as mono-sodium glutamate (MSG), which only further complicates our understanding of nutrition.
Modern farming practices, cultivars of plants, and breeds of animals sacrifice micro-nutrient content for economy in the form of macro-nutrient content. In some cases, you don't even get more macronutrient, but just more water content for the check-out scale. Thus you have the paradox of a person who is obese yet simultaneously starving thanks to a diet of soda pop and it comes about due to the imbalance in the ratio of micro-nutrients to macro-nutrients in the foods we eat. This is the tyranny of the middles aisles in the supermarket.
Now, the paleolithic principle is sort of like using a sledgehammer to pound in a finishing nail (HT: Chris). It works, it works quite well actually, but it is an excessive means to the task. I don't ascribe to the fairy tale view that everyone was engaged in happy-fun-time back before the introduction of agriculture but there's little doubt that hunter-gatherers were physically far more impressive animals than the more numerous agriculturalists and pastoralists that out-competed them.
It's clear to me that industrialization and technology has had a number of negative consequences to human health which we call the "diseases of civilization." The most obvious of these are heart disease, diabetes and obesity (including metabolic syndrome), but they also include autoimmune disorders (which are far more common than is generally recognized) as well as many neurological disorders. I don't think it has to be this way, but there have been some very wrong-headed paths taken in the field of nutrition over the past fifty-odd years.
From an evolutionary perspective, the more recently a particular foodstuff was introduced, the more likely it is to cause distress. This implies that refined oils and large quantities of fructose, both of which were entirely absent in the 1800s, are two of the more obvious places to eliminate and cut-back in order to restore the good health nature intended us to have.
If I were to sum up a reasonably brief list on what to do and what not to do, this would be it:
- Control appetite hormones like gherlin by eating regular, satiating meals. By satiating I mean protein, fat, and fibre. Try to avoid snacking.
- Restrict fructose and alcohol consumption to reasonable levels, day-to-day. 20 g/day of both combined would be a very healthful level, 50 g/day is I think an upper bound for people with healthy livers.
- Eliminate industrial, refined oils, particularly refined polyunsaturates such as soy and canola oil. Go for fresh and high quality fats, in particular clarified butter, extra-virgin coconut oil, extra-virgin olive oil, and the fats from animals fed their native diet. Unstable oils should be stored in the refrigerator or freezer to prevent them from going rancid, e.g. Omega-3 fish oil capsules. Most industrial oils are deodorized to prevent you from smelling when they go bad.
- Eat more than just muscle meat from an animal. Have you eaten liver pate or roasted heart lately? Bone broth?
- Fast occasionally for approximately 24-hours to give your liver a break and restore insulin sensitivity. Many religious groups noted for their good health (i.e. Seventh-day Adventists, Mormons, and the Greek-Orthodox of Crete and Corfu) regularly fast — is the the shared common trait. Fasting and starving are not the same thing, don't conflate the two.
- Go on elimination dietary trials of the common food allergies: wheat (including barley and rye), cow dairy, legumes, especially soy and peanuts, tree nuts, eggs, fish, and shellfish. Test assays may be insufficient to recognize many of the idiopathic problems (i.e. autoimmunity, neurological disorders) that these types of food may induce. It took me six months wheat-free to get better.
- Supplement with Vitamin D, on the order of 1000 IU/12 kg of body mass per day. Consider that the recommended doses for infants are 400 IU/day, so if you mass ten-times that of an infant, you need ten-times as much vitamin D; recommended adult doses are a joke. Also consider that you produce about 10,000 IU/ 30 minutes in full-sun. Vitamin D is not a vitamin, it is the precursor material to most of the steroid hormones in your body. When the endocrine (hormone) system has adequate signaling compounds, the whole body works better.
You may have noticed that I haven't talked about exercise at all, and that's because I think it is relatively unimportant. If you apply the 80/20 rule to how well you feel, I think perhaps 80 % of your wellness comes from diet, 15 % from adequate restful sleep, and perhaps 5 % from physical activity. Trying to lose body fat from exercise is a fool's errand and more than likely will result in over-training and the associated chronic injuries. While I personally do get a lot of physical activity, it's all for fun. My current hobby is whitewater kayaking, so any physical training I do is oriented towards improving my performance in that regime rather than building bulging biceps. I don't bother lifting weights in the gym since I find it quite dull. The fact of the matter is I got healthy through diet first and only then started exercising more.
Now, you may have noticed me talk about autoimmunity a lot and that is because I think it plays a key role in the diseases of civilization. Autoimmunity is simply the case in which the immune system, which is responsible for both healing and repealing foreign invaders, starts attacking the tissues of its host body. Autoimmunity has a genetic component, but something needs to trigger it. Examples are viral or bacterial infections, or dietary allergies. Celiac is one type of autoimmune disorder, type 1 diabetes is another.
If the diet is introducing strange, novel foreign bodies into the gut and the gut is compromised, they will penetrate into the circulatory system. The immune system sees these foreign bodies and goes berserk trying to hunt them all down and destroy them. Then, four to six hours later, you eat another meal and the cycle repeats. The solution is to remove the stimulus, i.e. fix the diet.
Any sort of food allergy or intolerance is likely to result in the immune system being depressed. The immune system only has a finite capacity for fighting infection, and if you're making it waste its time chasing gluten peptides or whatever, it is not going to be so strong at fighting off the latest pathogen. Similarly if you are not providing the immune system with enough micro-nutrients to operate at full capacity you will not only get sick more often, but you will also heal more slowly.
If I could sum up my nutritional philosophy in one sentence it would be:
Don't eat things that cause your immune system to run around like it has a hole in its head.A touch different from Michael Pollan, but I digress.