Well, here's my thoughts on it...
I haven't read the book but I've heard the theory, and I have to say that if your body allows your sugar levels to fluctuate so wildly that it affects your brain, you need to be checked for diabetes or hypoglycemia, because you almost certainly have one or the other. Your body does its utmost best to hold sugar levels in your brain constant; by the time your brain no longer receives a steady amount of glucose at the right level, your body has been suffering swings wide enough to cause serious physical illness.
Obviously, your body needs sugar to survive. If you don't eat sugar, it converts other foods into sugar. Pure sugar--sucrose, glucose, fructose, the kinds that are the closest to energy--can be damaging, but only in excess. It's damaging when you eat a lot of it at once, repeatedly, forcing your body to dump large amounts of insulin, which you can then stop responding as well to, causing diabetes. I've actually seen it happening in mice--give them sugar syrup to drink, and they will become diabetic. (Well, technically I looked at the numbers sent to my computer by their telemetry equipment. I never actually saw the mice. Modern science, go figure.)
If you're constantly pounding your body with sugar, you will end up messing up your body's digestion of sugar before it can start doing anything to your brain. I can agree that if you are diabetic or hypoglycemic you may have some mental effects. If you're not, though, your body is by definition handling the sugar you put into it well enough that your brain should be getting the usual amount of glucose which it runs on.
You may, if you eat too much sugar and not enough more slowly-digested energy sources, end up with general ill health. But before your body's sugar-regulation system breaks down altogether, you're unlikely to feel effects other than indirectly, because the wall between the brain and the rest of the body keeps the brain in a much more careful homeostasis than the rest of you.
05 Sep 2009, 5:53 pm
