Beans, Greens, and the Best Foods for the Brain

Bret S. Stetka, MD


July 07, 2015

In This Article

The Evolution of the Human Diet

Dr Deans then took the mic took to explain how evolution has shaped the human diet. "Hominid diets have changed drastically through millions of years of evolution. We started with plants, insects, and larvae; but around 2 million years ago we began incorporating meats into our diets, contributing to the development of the advanced hominid brain," she explained. "Then 1 to 2 million years ago we added tubers and bulbs. Finally, around 6000-10,000 years ago, agriculture was developed and we added grains, dairy, and legumes to our diets."

But only in the past 100 years has our diet drastically switched from a whole foods diet to one that is more processed and high in refined carbohydrates; that includes more vegetable fats rather than meat fats; and preservatives, emulsifiers, and other additives, which appear to have contributed to a decline in our collective health.

The backstory of 20th century grain processing, specifically, is an inane one. Once-nutritious kernels were stripped of their nutrients as new refining practices emerged, only to have specific vitamins added back artificially, given the health problems associated with overly refined grains. Grains and other foods have been processed and preserved for thousands of years, but by using much healthier means. For example, fermentation of grains—and letting them sprout—increases nutrient availability.

The first quiz question then flashed on the screen: What food group is most closely associated with Homo sapiens' brain evolution?

Answer: Shellfish.

Early humans evolved in the African Rift Valley, which is near a seacoast. It's possible that whatever evolutionary spark occurred that made us human occurred here, in part due to reliable access to seafood—oysters in particular—which glutted our brains with omega-3 fatty acids and cholesterol (our brains are composed of 60% fat).

Oysters and other mollusks are also very high in nutrients, including B12, which is commonly deficient in people consuming vegan or vegetarian diets and is necessary for myelin and neurotransmitter function. As Dr Deans pointed out, oysters can be an option for some people avoiding meat for moral reasons; oysters don't have a highly developed nervous system, so if they do feel pain—and many scientists believe that they may not—it's most likely scant.

Dr Deans then pointed out that despite focusing on specific nutrients or foods when considering nutrition, there has been a refreshing and hopefully more effective trend recently among experts to focus the influence of dietary patterns on brain health. Enter the Mediterranean diet.


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