Sunday, September 15, 2013

RAW FOOD DIET, DR. WEIL, AND YOUR BRAIN





I've recently had a number of messages from clients and Facebook fans asking questions about an article they saw on Dr. Weil's website about a raw food diet. 

The article is entitled "Raw Food Diets and Your Brain". And it starts by telling us to "think again" if we are considering a raw food diet. It talks about one study done in Brazil that looked at how our brains evolved beyond gorillas and chimps. The Dr. Weil article made erroneous assumptions in concluding that our brains evolved because our ancestors learned how to cook food.

Please remember to be a critical thinker and also always check your sources. For one thing, the article on Dr. Weil's website makes the statement that  "If humans ate only raw foods, the researchers calculated, we would have to eat for more than nine hours straight in order to get enough calories to sustain the energy requirements of our bigger brains."

But, the study does NOT say that.  In fact, it doesn't refer to a raw food human-suitable diet at all. Instead, it says 

"on a raw diet similar to that of extant nonhuman primates, Homo species would be required to feed consistently more than 9 h/d to afford their estimated MBD and number of neurons." 

The key point in that sentence being a diet "similar" to nonhuman primates. Not the more generic Dr. Weil term, "raw food diet", which would mislead many readers into thinking that it applies to what those of us in the raw food community actually eat.

The reason that is extremely important is because if you look at the diet for nonhuman primates, it is mostly greens. Mountain gorillas "mostly eat foliage such as leaves, stems, pith, and shoots of terrestrial herbaceous vegetation. As a rule, high protein foods which are low in fiber and tannins are preferred. They will also occasionally eat fruit, but this only makes up a very small part of their diet."  Lowland gorillas eat slightly more fruit, about 25%.

So, clearly, any human who has the idea of surviving on greens and herbs with a tiny amount of fruit would no doubt be required to eat pretty much nonstop because of the dramatically low caloric value of greens. That's not news. What was shocking was that the Dr. Weil article made such a giant leap by stating that a primate diet of almost all low calorie greens, would be anywhere near the same as a human raw food diet that includes a lot of fruit, higher calorie starch vegetables like yams and potatoes, as well as nuts and seeds which are EXTREMELY calorically dense.

Most important, is that the whole point of the study from Brazil was NOT about nutrition. It was NOT about what is a healthy diet for humans. In fact, it had nothing to do with that. 

It was a study done on the neurons in the brain, and a process called encephalization... developing large brains. The researchers set out to study and understand why humans have smaller bodies and larger brains, while other primates have much larger bodies and smaller brains. 

Their conclusion? It is NOT because of eating meat, it is NOT because of cooking, but it IS because of the ability to consume MORE CALORIES, since our brain tissue is energetically expensive tissue.

What the study truly says about cooking is that with the advent of cooking, our ancestors were able to get more calories in less time. "metabolic limitation was overcome in the human lineage by the advent of cooking food, which greatly increases the caloric yield of the diet, as a result of the greater ease of chewing, digestion, and absorption of foods." 

Clearly, with a huge percentage of our modern day humans being obese, I don't think we have to worry about the need to "increase our caloric yield". In fact, it's quite the contrary. A million years from now scientists will be studying that time (2013) when their ancestors (us) followed peculiar calorie-restricting starvation diets to reduce the size of their bodies with the use of fake foods, fake sweeteners, and an oddly bizarre behavior known as "portion control".  

Moreover, the study says that cooking allowed our ancestors to eat very high calorie foods such as meat, because "raw meat is difficult to chew and ingest".  Well, that's not news either. Of course raw meat is extremely difficult to chew and digest for humans  -- we don't have carnivorous teeth or short digestive tracts required to digest meat of any kind, let alone raw!

Ultimately, it' all conjecture anyway. You'd have to rely on an awful lot of assumptions and missing links in logic to even agree with the whole premise that someone making a hypothesis today in 2013 can even remotely have a clue of what was going almost a million years ago, when the oldest generally-accepted evidence for controlled use of fire by humans first occurred. (It was at the site of Gesher Benot Yaacov in Israel).

Additionally, even among people who do promote and eat 100% raw today, they typically consume far more calories than their cooked counterparts. Most of them easily consume 2800-3000 calories or more in a day, and are certainly not eating for 9 hours straight. Many of them are endurance athletes who eat a primarily fruit based diet. While I personally do not believe that is the optimal long-term diet, they clearly are not sitting down to meals for 9 hours. Sitting down to 10 persimmons or 12 bananas is a typical meal. That doesn't take 9 hours, and is a lot of calories.

When you eat a raw or high raw diet, the volume of food is in fact quite large compared to cooked, dead, devitalized high calorie animal foods, or even low quality plant foods. This can be very challenging initially for a person who is used to eating a 100 calorie snack pack of fake food, or a piece of animal meat loaded with fat. It is even challenging for many plant based eaters who eat a lot of devitalized food, such as small packs of processed seitan and carefully measured portions of wheat pasta, while diligently counting their calories to make sure they don't go over their starvation level 1200 calorie diet.

Ultimately, I encourage you to READ the actual study from Brazil that the Dr. Weil article was based on.  Sadly, the article took one study, drew a few non-evidence based conclusions, and wrote a factually inaccurate article. It's unfortunate, but common.

Many of us who are interested in eating raw foods are interested in the cancer-fighting, heart disease fighting, and diabetes fighting health benefits of raw plant foods, building our muscles and cells from purely clean energy, supporting our body's natural buffering systems with foods that have an alkaline effect on the body after metabolism, and avoiding the acidity causing, inflammation promoting, putrefying effects of a dead, devitalized, animal based, gluten-containing, over-proteinized, processed, common diet. All while making food choices that are kind to the earth, animals and humans alike.

 



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