An interesting study which adds some evidence to the Insulin-Obesity theory (Pittas AG, Das SK, Hajduk CL, Golden J, Saltzman E, Stark PC, Greenberg AS, Roberts SB. A low glycemic load diet facilitates greater weight loss in overweight adults with high insulin secretion but not in overweight adults with low insulin secretion in the CALERIE Trial. Diabetes Care. 2005;28(12):2939–41.).
Two groups of people were put on two different diets. The two groups were matched and the diets were matched for calories. One of the diets was High Glycemic Index and the other was a Low Glycemic Index diet. The people who had higher fasting Insulin levels responded better to the Low Glycemic Index diet. The group with lower fasting Insulin levels responded to both diets in equal way.
The main finding from this pilot study was that healthy overweight women and men with relatively greater insulin secretion in response to a standard oral glucose tolerance test lost more weight when assigned to a low– glycemic load hypocaloric diet than to a high– glycemic load diet, but there was no differential effect of the two diets on weight loss in individuals who had relatively lower insulin secretion.