Sugar Makes You Stoopid

     Recently, Newsweek featured a cover story on obesity (in conjunction with an HBO special on overweight Americans) in which author Gary Taubes challenged the conventional wisdom that we get fat because we eat too much and don't get enough exercise. Taubes instead claims that certain foods, particularly refined sugars and grains, are the primary culprits in spreading the epidemic of obesity in America.

     I greeted this story with no joy. I, myself, am not a big meat eater. But I love cereal, bread, pasta. And at my local 7-Eleven there's a daily special. One donut costs 69 cents, but you get two for a dollar. So, you know ... just in the interest of fiscal responsibility, I usually buy two.

     Taubes acknowledges that fats and meats may cause other problems, such as higher cholesterol, but they don't make us gain weight. In fact, per capita red-meat consumption peaked in this country in the mid-1970s, before the obesity epidemic even got off the ground. Since then, consumption of red meat has steadily declined, while the consumption of carbohydrates has increased -- along with our weight.

     The problem is that carbohydrates carry the cheapest calories, and as Taubes says (and I have personally confirmed), "They can be plenty tasty without a lot of preparation and preservation." But the biology suggests that they make us fat, while other foods (fats, proteins, and green leafy vegetables) do not.

     Sugars, refined grains and starches affect the hormone insulin, which regulates fat accumulation. Both sucrose (the white, granulated stuff we sprinkle on cereal) and high-fructose corn syrup produce elevated levels of insulin, which in turn brings about a deleterious effect on metabolism and promotes the steady accumulation of fat in our tissue. (High and unstable levels of insulin are also a hallmark of type 2 diabetes.)

     Now comes along a new study from UCLA reporting that eating sugar not only makes us fat, but also makes us stupid. Researchers gave a fructose solution to rats and observed that they had more difficulty figuring out how to get through a maze than rats on a regular diet. When the brains of the sugar-fueled rats were examined, researchers found that their insulin was less effective in controlling blood sugar and regulating synapse function in the brain.

     Researchers found one partial antidote. Rats who had their sugar-coated diet supplemented with flaxseed oil and fish oils, both of which are sources of omega-3 fatty acids, were able to work their way through the maze faster than the rats who'd been given just the sugar solution.

Dr. Fernando Gomez-Pinilla of UCLA

     Says Fernando Gomez-Pinilla, professor in physiological science at UCLA, "Eating a high-fructose diet over the long term alters your brain's ability to learn and remember information. But adding omega-3 fatty acids to your meals can help minimize the damage."

     So what should we eat? The latest clinical trials suggest that all of us would benefit from fewer sugars and fewer refined grains (bread, pasta) and starchy vegetables (potatoes). Meanwhile, evidence suggests that diets that are severely restricted in fattening carbohydrates and rich in animal products—meat, eggs, cheese—and green leafy vegetables are arguably the best approach to controlling your weight, if not the healthiest diet to eat overall. Not only does weight go down when people eat like this, but heart disease and diabetes risk factors are reduced.

     So, on my next trip to 7-Eleven, I guess I'd better double-check my arithmetic. Or, I could pick up some broccoli on the way home.