The purpose of eating is to provide your body with nutrients. But since sugar is devoid of nutrients, the body must actually draw from its nutrient reserves to metabolize it. When these storehouses are depleted, the body becomes unable to properly metabolize fatty acids and cholesterol, leading to higher cholesterol and triglyceride levels. Drawing on the body's nutrient reserves can also lead to chronic mineral deficits, especially in magnesium (a mineral required for more than 300 different enzyme activities) and chromium (a trace element that regulates hormones such as insulin), putting you at risk for dozens of diseases, from depression to attention deficit disorder to asthma.

A recent study, for example, found that kids who eat significant amounts of junk food are much more likely to develop asthma than kids who don't eat junk food. While the researchers didn't tie asthma to sugar itself, they did point out that a diet full of candy and other highly processed junk foods is deficient in a number of nutrients essential to health. And as I explained earlier, such foods further deplete the body of nutrients once consumed.

In fact, children are the biggest consumers of nutritionally void junk food at a time when their brains and bodies are growing rapidly and in need of a nutrient-dense diet for proper development, both physically and mentally. Criminologist Stephen Schoenthaler has been conducting nutritional studies on delinquents and public school children for almost thirty years. In a paper from 1986 he describes how one million kids improved their test scores when they eliminated sugar and white flour from their diets.

Alexander Schauss, Ph.D., a nutritional researcher and writer, performed similar work in juvenile detention centers and showed that violent behavior decreased dramatically when sugar was eliminated.

But I don't eat junk food. Why should I be concerned about my sugar consumption?
Unless you're eating a diet entirely made of whole, unprocessed foods (think fruits, vegetables, grains), you're probably eating more sugar than you think, and than you should. Sugar, in its myriad forms, is added to virtually every packaged food product you'll find at the supermarket - not just the sweet stuff. If you drink one soda, even the "natural" variety, used up your day's sugar allowance.)

Don't be fooled by the ingredients list. Sugar has hundreds of pseudonyms (see "Stealth Sugars," for a sampling), and manufacturers have gotten very good at hiding them from consumers. Because ingredients are listed from most to least amount, often three different types of sugars will be in the middle of the list. If all sugars were required to be listed together, sugar would be the first ingredient.

To find out how much sugar you're actually taking in, try keeping a food diary for one week. Check the labels of the foods you eat and make note of their sugar content. The reality of the numbers may not hit home because most of us don't think in grams - 4.2 g of sugar is equivalent to 1 teaspoon of sugar. At the end of the week, take the total number of sugar grams and divide it by 4.2 to get your weekly sugar intake in teaspoons. Then divide that number by 7 to get your daily sugar consumption.

Unfortunately, the way the FDA's labeling rules are set up, manufacturers don't have to separate added sugars from naturally occurring ones on labels. But your total sugar intake will give you a very good idea of how much added sugar you're eating. Naturally sweet foods, such as fruit, don't really contain that much sugar. A cup of strawberries, for example, contains 1/6th the sugar of a can of cola.