We Are Not Gorillas

N.B. - *I have included the vegan tag because I would appreciate some respectful feedback from practitioner regarding this post. *

For the last six months, I have been re-exploring nutrition. I have come across several documentaries, web sites, and exhorting an entirely plant-based diet and even a plant-based raw diet. They generally say that we should eat as do our primate cousins, in particularly, the gorilla is used as an example. One article I read recently even suggested not to drink water, but, instead, to intake the necessary water for proper hydration using raw fruits and vegetables.

Unfortunately, these are fads. They ignore evolution and human biology.

It's SAD

I actually empathize with vegans and various vegetarians. The Standard American Diet (SAD) is detrimental to one's health. We consume too many carbohydrate calories, particularly of the more empty variety. We consume too little fiber and essential nutrients. We consume too many calories from animal sources.

This means that the SAD lacks sufficient quantities of essential nutrients. Essential nutrients are those that we cannot produce (or produce too little of) and must be provided via diet. For exmaple, omega-3 fatty acid (DHA and EPA) cannot be produced by biologic mechanism within humans. Similarly, vitamin C cannot be produced and, therefore, must be consumed.

Certainly, the best way to get essential nutrients is from natural sources. We have evolved to extract these nutrients from these sources. Additionally, vitamin supplementation via fortifird foods or pills and elixers are problematic. The bioavailability and bioequivalence and supplements lack standard definitions and, therefore, may not be useful to the degree desired.

So, Vegan is a Reasonable Diet, Then?

While it's probably true that vegan is better that SAD, it is certainly not an ideal diet. There are nutrients that can only be obtained in sufficient quantities via animal sources. Also, there is one, vitamin B12, that can only be obtained naturally from animal sources.

A study from Annals of Nutrition & Metabolism found that, for vegans that did not supplement, 92% showed B12 deficiency and while lactovegetarians showed 64% deficiency. The least deficient, at 20%, were the semivegetarians.

Another nutrient that is problematic for vegans is DHA, and to a lesser extent, EPA omega-3 fatty acids. Many vegans get their omega-3 fats from sources such as flaxseed oil. However, the omega-3 fat from plant sources is the ALA variety. ALA is used mainly for energy and conversion to EPA and, particularly, DHA "appears to be unreliable and restricted." This is particularly important since low blood level of DHA and EPA are associated with increased risk of death from coronary disease.

The typical vegan will say, "Look to our primate cousins, such as the gorilla, and you will see what we should eat."

I say that, if we are to look to other primates for dietary guidance, we should look to our closest cousin, the chimpanzee. Chimpanzees are omnivores. According to Jane Goodall's observations, 5-8% of a chimpanzee's diet is meat and eggs. And they are not just meat eaters, they are hunters.

Like chimpanzees, humans have evolved over at least 1.5 million years to consume food from animal sources. The consumption of meat allowed our evolution of larger brains. Another indication of our evolutionary transition to omnivores is our weaker jaws and smaller intestinal tracks than our vegetarian cousins. Our intestinal track is about 60% the weight than would be expected were we like gorillas.

What should we eat?

It appears that the SAD and vegan diets both miss the mark. The SAD relies too heavily on animal sources and, often, the fruits and vegetable consumed are over processed. The vegan diet completely ignores our evolution and biology by eliminating animal sources altogether. So, where is the balance?

To understand, we should look to hunter-gatherers. One study estimated that the ratio of plant to animal consumption is 65:35. Some hunter-gatherer societies, such as the Inuit, would depend to a greater degree on hunting since the opportunity for gathering would be more restricted.

So, enjoy steak, salmon, or a pork chop. Just be sure to include a salad and some steamed broccoli and carrots or asparagus. Just stay away from deep fried foods.

Final Note

Regarding raw vegetables, it is true that cooking them will cause a loss of some nutrients. However, some vegetables also release other nutrients when cooked. A prime example is the tomato. A cooked tomato will lose some of its vitamin C, but will increase its lycopene, a powerful antioxidant. Since vitamin C is available from many sources, the loss by cooking a tomato is not a problem.