Tuesday, 19 January 2010

Gluten, casein, running and thinking

I have stumbled upon an article "Perceptual Pleasure and the Brain" by Irving Biederman and Edward Vessel discussing the role of endorphins in cognition. It appears that our brain craves novelty, and learning is associated with pleasure via opioid receptors in the brain. This can be a mechanism for survival and for evolutionary success.

What the authors do not discuss is the possible habituation of opioid receptors by continuous stimulation. This can be the result of addiction to drug opiates, but we also know that gluten and casein break down to peptides which bind to opioid receptors in the brain. This is one reason why we crave these foods after all. Interestingly, long distance running or cycling on a regular basis also releases endorphins, leading to mild addiction (I experienced this myself).

Now, with our receptors desensitised by grains, dairy and threadmills, we might need stronger stimulation to enjoy learning or we lose interest in learning altogether.

Opium for the masses?

If indeed the dietary derived opiates have any significant impact on brain function, it would explain why Paleo people are so hungry for knowledge, as evidenced by the high calibre discussions on blogs such as WholeHealthSource, Panu or FreeTheAnimal :)

Perceptual Pleasure and the Brain
http://www.americanscientist.org/my_amsci/restricted.aspx?act=pdf&id=3718998800815
(If you Google the title you can find the full text of other sites, such as:
http://condition.org/as65-6.htm)

Regarding food and thought, I have been thinking a lot about the possible POSITIVE impact of high carbohydrate diet (even with the harmful effects of grains) after the Neolithic revolution. I imagine that glucose (though not fructose) loading can be very good for brain FUNCTION short to medium term (before the degeneration sets in). Brain thrives on glucose and can be turbo charged with more carbs in the diet. Even if that would not mean optimal HEALTH overall, it could mean more brain power for competitive advantage! The analogy would be that maximum fitness does not equal otimum health and longevity (as brilliantly laid out by John Little in Body by Science). For the same reason using stimulants, such as cocoa or coffee (and sugar too!), can translate into more effcient thinking, better strategic planning? Something that the carb lobby can consider in their PR :)

4 comments:

  1. Very insightful post. We need a better understanding of the link between evolutionary pressures and paleo nutrition. Not everything is as simple as it looks, as shown by your post.

    This brain response to glucose may indeed be an adaptation that, while not very good for the individual’s health in the long term, may actually improve reproductive success in the short term.

    That is, this may be an evolved handicap, or costly trait.

    Coincidentally, I have just posted on this topic, and its relationship to strict paleo dieting.

    Take care, Ned

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  2. Hi. Pretty interesting posts you are putting out. Good job, looking forward for the next one!

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  3. Psychostimulants of course, do just what you are discussing. I'd be interested in the dopamine connection, whatever it is, to glucose loading. And I wonder if paleolithic eating makes a person more dull witted?

    Indeed it is complex, but I am reassured in more opaque moments by the knowledge that everything is connected to everything, so what I don't "get" today, will be not far off from what I do get, and everything I do get contributes to more complete understanding.

    Given enough time, of course.

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  4. Indeed, it is my working hypothesis that Paleo eating makes you more dull witted, perhaps less abstract thinking. But I see no evidence supporting this, just playing devil's advocate.

    On the other hand, fasting/ketosis is supposed to make you more clear thinking, more focused, more imaginative. This is why ancient philosophers and speakers fasted for a few days before their performances. This could be different longer term, which is perhaps why going in and out of ketosis is more natural and you get the best of two worlds.

    What is more likely though, is that our civilisation evolved with class structures with different foods for different classes. The kings and nobles hunted while the peasants toiled on gruel and bread. The soldiers were getting plenty of meat. Peasants were not expected to think independently. Kings had to think strategically and soldiers tactically.

    Yet some will say that it is the very diet, rich in grains/carbs, which allowed humans to make a move from small hunting bands to grand civilisations. Grains = complex social structure. I do not think to be the case, there is only association, not causality, as evidenced by Colin Renfrew in "The Making of the Human Mind". It was the sedentism which cas crucially important in turning us into complex social animals with rich culture. Sendentism was associated with agriculture but did not have to be. The Cro-Magnon and even early Megalithic people were sedentary but did not farm land. I think eating fish was an easy way to stay at home longer and have planty to eat (apparently ancient Britons ate huge amounts of fish until about 5,000 years ago, when they started to experiment with farming and breeding animals).

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