Sunday, September 28, 2008

"Everything" in moderation?

People like to make the case that humans are omnivores. Now literally, that means "eats everything", but in the textbook sense, it just means we are not strict carnivores or herbivores. We are adapted to eat some vegetation and other animals, not "everything".

To prove this to yourself, imagine being dropped in the wilderness, anywhere on earth away from civilization. I live in Montreal, so I like to take the example of a boreal forest, typical of my latitude.

In the summer, the land around you would be teeming with life, but the greatest portion of it would be unavailable to you: bushes, trees, and grasses -- you couldn't digest maple leaves or pine cones. If you were lucky you might find a few wild berries. If you knew what to look for, you might find some edible roots and herbs. If you were quick enough or smart enough, you might be able to catch a fish or bird, or other wildlife -- in other words, you would face the same challenges as any hunter-gatherer. And you would be eating the very foods your body was designed to eat.

So remember that the omni in omnivore stands for: a preciously small fraction of what we can digest and thrive on. Moderation need not apply to this group of foods. In fact, if restricted to these food choices you could eat as much as you want. This is what our ancestors did, and they did not suffer from obesity and other "diseases of civilization".

When we talk of moderation it's usually in the context of modern (post-agricultural) food, or just things which can make you ill in the short term, like alcohol, or sugary drinks. But then you run into the problem of figuring out what a moderate amount is. Is it two beers a day, or three? One Coke or two? What is a moderate amount of rice or other grain? Of saturated fat? Do we judge by how much we can tolerate in the short term without becoming ill, or is there a long-term risk?

I believe that when an animal eats its natural diet, its portions are moderated and regulated by its body, and the feedback mechanisms which govern hunger and satiety. This is what we observe in nature.

Feed it something it is not adapted to, in sufficient quantity, and it will ultimately get sick. This is what we observe in modern human civilizations.

Night sweats and sweets.

In the last eighteen months of low-carbohydrate eating, I have completely enjoyed the freedom to eat any amount of food I desire. My experience has shown me that the body does indeed regulate its weight via hunger and satiety signals, but only when consuming the proper diet.

However, my freedom to consume has been abused on occasion. I can remember four times involving birthdays and barbecues, where I really packed in the protein. And each time I paid for that gourmandise in the middle of the night: waking up hot, sweating, and with a rapid pulse.

From what I have learned about our biochemistry on low-carb, I think this makes sense. When insulin levels are kept low, fuel calories cannot be stored, so the body has no choice but to burn them. Thus, the night sweats: you take in extra fuel, the motor runs hotter.

It occurs to me that had I wanted to avoid this midnight punishment for gluttony, there was always an antidote: dessert!

Yes, by ingesting a huge whack of sugar, I could trigger my pancreas to work overtime and flood my bloodstream with insulin. This would have the effect of pushing a large quantity of calories into my fat tissue, and spare me the mild overnight "food fever."

I am ready to believe that our custom of eating sweets at the end of a meal is a direct result of this phenomenon experienced by our ancestors. If one is fortunate enough to have a lot of extra food and access to sugar (the combination of which, about a hundred years ago was available only to the wealthy) it sounds like the perfect fattening plan. Now, I don't know if this is a biological "just-so story", but it makes sense to me.

Friday, September 19, 2008

Putting two and two together?

I came across two articles in the same issue of The Peninsula, Qatar's English language daily.

In the first, we read that Qatar is no different from almost every other modern country in becoming alarmed at the national obesity rates [full article]:
"Around 40 percent of school children in Qatar are obese, according to Dr Mahmoud Al Zari, Director of Diabetes and Endocrinology at Hamad Medical Corporation..."
In the second, they are pleased to report a confectioners' trade show [full article]:
"Qatar has developed quite a sweet tooth as data show the market for sweets and confectionery grew by 23 percent in 2007, just behind Saudi Arabia, which registered a 24 percent increase."
Here is another case where we see increases in obesity alongside increases in sugar consumption. So what does the first article conclude?
"Bad foods are those with high fat content. Fatty foods cause heart burn and acid reflux."
Well, that's zero out of two correct.