Oh, no, not another new diet! That's what I thought when I heard about this one. But it turns out it's not new-it's been around since the mid-1980s and the well-known South Beach diet is based on it. More important, it just may be the smartest food plan yet. They're calling it the Low Glycemic Index diet, or Low GI (not to be confused with lower GI for gastrointestinal).
The glycemic index is a score originally created by David Jenkins, MD, PhD, of the University of Toronto, as a tool for diabetics to help manage their blood sugar. It is a ranking on a scale from 0 to 100 of the carbohydrates (starches and sugars) in a food for the extent that eating it raises your blood sugar level. Here's what it tells you: Not all carbohydrates are created equal.
Foods with a high GI are rapidly digested and absorbed (such as processed foods made with white flour and sugar). Blood sugar levels spike quickly, then fall rapidly, distressing the body in many ways, including affecting insulin and alerting the body to store fat.
"Low GI foods, by virtue of their slow digestion and absorption, produce gradual rises in blood sugar and insulin levels, and have proven benefits for health," says Jennie Brand-Miller, PhD, author of The Low GI Diet Revolution and a professor at the University of Sydney (Australia), School of Molecular and Microbial Biosciences.
Recent studies from Harvard's School of Public Health indicate that the risks of diseases such as type 2 diabetes and coronary heart disease are strongly related to the GI of the overall diet as well. "In 1999, the World Health Organization (WHO) and Food and Agriculture Organization (FAO) recommended that people in industrialized countries base their diets on low GI foods in order to prevent the most common diseases of affluence, such as coronary heart disease, diabetes and obesity," says Brand-Miller on her website.
Foods with a low GI (under 55) include most vegetables, fruits and whole grains. Meat is not a carbohydrate, so it does not have a score, and dairy products, which do have sugars, tend to score low as well, though they may be high in fat. As you might have guessed, "junk foods," cakes and cookies have a high GI.
For a GI database for specific foods and more information, visit www.glycemicindex.com.