Food for a GL Diet

GL or glycemic load diets advocate considering the glycemic load value of foods consumed at each meal rather than total carbohydrates or calories as part of a weight loss program. The glycemic load of a food type comes from considering the food's glycemic index value and the amount of carbohydrate in the food according to Merck Online Medical Library. Low glycemic index foods eaten as part of a GL diet digest more slowly than high GI foods thus having less impact on blood sugar and insulin levels.

History

The belief that carbohydrates, rather than fat and protein, were significant culprits in weight gain received prominence with the publication of Dr. Robert Atkins' book "The Diet Revolution" in 1972. Interest in restricting dietary intake of carbohydrates soared in the late 1990s and early 2000s with the publication of Atkins', "New Diet Revolution" and Dr. Arthur Agatston's, "South Beach Diet". According to Johanna Burani, MS, RD, CDE writing for "Diabetes Health," the glycemic index resulted from early work by David Jenkins, MD, PhD, a professor of nutrition at the University of Toronto, Canada, who began scientific testing of changes in blood glucose levels in response to specific foods. The work of Dr. Jenkins and other scientists led to the creation of the glycemic index. GL diet foods extend diet considerations by incorporating the amount of carbohydrate in a food in addition to its GI value.

Calculating

To calculate the glycemic index of a food, scientists feed a fasting test subject sufficient quantity of the food to equal 10 to 50g of carbohydrate. They measure blood sugar values at 15 to 30 minute intervals for two hours for the test food compared to pure glucose yielding a sugar response curve for comparison. Using an example from Florida State University, brown rice raises blood sugar only 55 percent as much as glucose raises it. Therefore, brown rice has a GI value of 55. To calculate a food for inclusion in your GL diet, you multiple the GI value times the quantity of that item on your menu divided by 100. Food with a low GI index value such as meat will have a low GI load. However, high GI value foods may have a high or low GL depending on the amount of available carbohydrate per serving.

Factors

According to Merck Online Medical Library, several factors affect the food on a GL diet including grinding and processing, which raises GL. Therefore, shredded carrots would have a higher GL than a whole carrot eaten raw. Cooking can raise the GL of some foods such as pasta. The fiber content of a food decreases its GL because the slow digestion and the sugars absorb more slowly. Riper fruits have a higher GL than less ripe ones. Eating GL foods with a fat or acid slows digestion as well as slows the absorption of sugars.

Types

Carbohydrates, proteins and fats make up all of the food we eat in different proportions. Foods with only proteins and fats do not have GL values. Therefore, meat, fish, poultry and olive oil for example become low or zero GL foods. Foods with carbohydrates have a GL factor. You can find out the GL of many processed and whole foods through the Gylcemic Index Foundation's database.

Considerations

Eating several small meals a day that include protein and fat along with carbohydrates offers a lower GL over the day than one large meal. Drinking a glass of water before a meal correlates with eating less and greater weight loss. Study the GL values of foods and then remove from your pantry -- and temptation -- those with high GL values.