Those promoting the Paleo Diet argue that humans are genetically wired to eat meat, foraged vegetables, fruits, nuts, and seeds. Paleo peoples, they argue, did not eat grains, legumes, or dairy.

Loren Cordain, The Paleo Diet Cookbook, is a professor in the Health and Exercise Science Department at Colorado State University. Cordain focuses on the evolutionary and anthropological basis for diet, health, and well-being in modern humans. Cordain is generally acknowledged to be the world’s leading expert on the Paleolithic diet. He has analyzed 229 hunter-gatherer societies and published more than 100 peer-reviewed publications.

Robb Wolf, The Paleo Solution: The Original Human Diet, is Cordain’s student. Wolf is a former research biochemist who now co-owns the NorCal Strength & Conditioning gym, ranked by Men’s Health as one of the top 30 gyms in America. Wolf explains why grains are so hard for humans to digest and how they foster a “leaky gut” condition which, in turn, leads to an array of chronic diseases, including neurological diseases like Multiple Sclerosis and Parkinson’s.

Dr. Terry Wahls, Minding My Mitochondria: How I Overcame Secondary Progressive Multiple Sclerosis ( MS) and Got Out of My Wheelchair, is a clinical professor of medicine at the University of Iowa. In 2003 she was diagnosed with MS and soon became wheel-chair bound. When mainstream medicine could not slow her disease, she started to research how nutrition could help. Within eight months of starting a Paleo diet, she could walk again with a cane. Today, she rides her bike, rides horses, and lectures worldwide on what she has learned.

Google “Terry Wahls TED” (The Technology Entertainment and Design) and take a look at her short, informative lecture at a November 2011 TED conference.

“Hunter-gathers, pastoralists, and agriculturalists have been extensively studied since the mid-1800s,” notes Robb Wolf. Archeological evidence, he explains, demonstrates clearly that Paleo people were superbly healthy. Their bones, explains Wolf, “looked like those of high-level athletes.”

Paleo peoples, Wolf notes, “were as tall or taller than modern Americans and Europeans, which is a sign they ate a very nutritious diet. They were essentially free of the cavities and bone malformations that are common with malnutrition. Despite a lack of medical care, they had remarkably low infant mortality rates, yet had better than 10 percent of their population live into their 60s.” The Paleo peoples were “virtually free of degenerative disease such as cancer, diabetes, and cardiovascular disease. They also showed virtually no near-sightedness or acne.”

With the shift to agriculture, humans “lost an average of six inches in height,” writes Wolf. These early Neolithic farmers had about seven cavities on average per person. And, they had bone malformations typical of infectious diseases and did not live as long. Deficiencies in iron, calcium, and protein were common. Infant mortality rates increased.

Wolf notes that if the timeline of human history is compared to a 100-yard football field, the first 99.5 yards comprises all of human history except for the last 5,000 years. In the last 10,000 years, most humans transitioned from a hunter-gatherer lifestyle to the settled agricultural lifestyle of the last 5,000 years. Television, the Internet, and refined vegetable oils, notes Wolf, only take up the “last few inches” of this timeline. Surely, I think, the last quarter-inch would include today’s fake, franken foods.

In essence, explains Wolf, humans “moved from a nutrient-dense, protein-rich diet that was varied and changed with location and the seasons to a diet dependent upon a few starchy crops. These starchy crops provide a fraction of the vitamins and minerals found in fruits, vegetables, and lean meats. These ‘new foods’ create a host of other health problems ranging from cancer to autoimmunity to infertility.”

Our health researchers, Wolf argues, lack a scientific framework from which to study and assess information on what we should eat, so their answers “change in response to politics, lobbying, and the media.” I would add two other factors: individual economic self-interest (paycheck scientists and those who personally benefit from promoting certain diets) and the presence of a personal belief system not grounded in science, such as “salt is bad.” As a result, Wolf argues, “our `health maintenance system’ [is] more parasitic than symbiotic…. After all, it’s hard as hell to make money off healthy people….”

With some small exceptions, the following diets are closely related to the Paleo Diet: Dr. Natasha Campbell-McBride’s “Gut and Psychology Syndrome,” or the GAPS, diet; Gary Taubes’ Why We Get Fat,” which advocates the diet used by Duke’s Lifestyle Medicine Clinic; Konstantin Monastyrsky’s “Fiber Menace,” and Dr. Joseph Mercola’s “No Grain Diet.”

The above diets agree that grains are a problem. Where diversity emerges is over whether or not to eat legumes and dairy and, if so, which legumes and what kinds of dairy.

Be aware that whenever we attempt to adopt food ways from other eras or other regions, we inevitably bring our own belief systems into the mix. Cordain is no different. His emphasis on lean, grass-fed meat betrays the anti-saturated fat campaign that has permeated our culture since the 1970s. Of course early people ate animal fat; it was the only fat they had unless they lived near coconut trees or the sea. Eskimos lived mostly on fat and were supremely healthy.

Cordain’s anti-salt stance also betrays the presence of belief system, not science. Healthy salt is essential for humans and for preserving food. See Mainely Tipping Points Essay 38 on my blog.

Cordain recommends using dried egg whites in smoothies as a protein source. But, the scientists at the Weston A. Price Foundation argue that powdered protein powders of all kinds have broken chemical structures and are dangerous. Also, egg whites contain enzyme inhibitors that interfere with protein digestion. We need the egg yolk to digest the egg white, and the egg white needs to be cooked.

Cordain gets into trouble with his “non Paleo” diet list. He allows olive, coconut, avocado, walnut, macadamia, and flaxseed oils. But, most nut/seed oils are highly refined and, thus, dangerous. Unrefined coconut oil is a splendid choice for every use. High quality olive oil is all right if used in moderation and if not heated very much.

Cordain allows lemons and limes to season salad greens, but vinegar is not allowed. Yet, wine is. Vinegar and wine are the same thing essentially. How many Paleo folks had access to lemons and limes? Diet sodas, which are toxic chemical brews, are allowed.

I have stopped eating grains with gluten, am avoiding grains in general, and avoid legumes as it’s clear my body does not like them and because they are an inferior protein source. Dairy I love, especially fermented dairy like yogurt, kefir, and piima. There are many ancient peoples still present today who thrive on real milk. The Laplanders (reindeer), the Masai (cows), and the grasslanders from inner Mongolia (sheep) spring immediately to my mind. But I recognize that some people cannot tolerate dairy.

I believe the essence of the Paleo diet — grass-fed, free-range meats; wild fish; wild seafood; vegetables; fruits; nuts; and seeds — to be healthy. Medically, this way of eating can heal and support the body. Just ask Dr. Terry Wahls.

Louisa Enright lives in Camden.