From:	"USANA Health Sciences"
Date:	Jun 9, 2011 11:33 AM
Subject:	Glycemic load is a better predictor of glycemic response than
carbohydrate content alone - Weekly Essentials of Health Update
June 8, 2011
Glycemic load is a better predictor of glycemic response than carbohydrate
content alone
At a Glance
A new study provides evidence that the glycemic load of a meal is a better
predictor of blood glucose and insulin response that simply accounting for
total carbohydrates.
Read more about this research below.
The glycemic load (GL) is a ranking system for carbohydrate content in food
portions based on their glycemic index (GI) and the portion size. Glycemic
load for a single serving of a food can be calculated as the quantity (in
grams) of its carbohydrate content, multiplied by its GI, and divided by
100. While GL is increasingly used in nutritional research, its ability to
predict postprandial (after meal) blood glucose and insulin response for a
wide range of foods or mixed meals has been unclear.
In a recent issue of the American Journal of Clinical Nutrition, researchers
sought to assess the degree of correlation between calculated GL and
observed glucose and insulin responses in healthy subjects consuming
calorically identical portions of single foods and mixed meals.
In study 1, healthy subjects consumed 240 calorie portions of 121 single
foods in 10 food categories. In study 2, healthy subjects consumed 480
calorie servings of 13 mixed meals. Foods and meals varied widely in
macronutrient content, fiber, and GL. Blood glucose and insulin responses
were measured and compared to a reference food (= 100).
Among the single foods, GL was a more powerful predictor of postprandial
glucose and insulin response than was the available carbohydrate content
itself. Similarly, for mixed meals, GL was also the strongest predictor of
postprandial glucose and insulin responses. Carbohydrate content alone was
predictive of the glucose and insulin responses to single foods, but not to
mixed meals.
The results of this study are the first to provide large-scale evidence of
the superiority of using dietary GL over carbohydrate content alone to
estimate postprandial glucose and insulin response in healthy
individuals.
Jiansong Bao et al. Prediction of postprandial glycemia and insulinemia in
lean, young, healthy adults:	glycemic load compared with carbohydrate
content alone. Am J Clin Nutr May 2011 vol. 93 no. 5 984-996.