ConscienHealth’s Ted Kyle reports on a systematic review and meta-analysis of glycemic index, glycemic load, and type 2 diabetes risk published in Nutrients by an impressive global group of nutrition scientists. Their conclusions are simple and powerful he says. Glycemic index and glycemic load are important markers of food quality. In fact they do an excellent job of predicting type 2 diabetes risk for individuals and for the population.
Almost 40 years ago, David Jenkins published the first paper to propose that the glycemic index of foods might be an important measure of nutrition quality. Back then, dietary guidance pointed to a low-fat panacea. Research continued quietly on the glycemic index. The pendulum swung from fear of fats to carbophobia. Sugar is the villain of the day now. But maybe the time has come for the glycemic index to bring a bit more objectivity.
Perhaps some of the energy that goes into vilifying carbs, sugar, soda, and other dietary goblins would be better spent directing people toward better carbs. “Don’t” has never been an especially effective tool for behavior modification.
Senior author on this new paper, Jennie Brand-Miller, explains the appeal of the glycemic index: “I liked the fact that it turned traditional nutritional science upside down. The old wisdoms were that sugars were bad and starches were good, but the GI showed some starches, such as potatoes, converted to glucose far quicker than some sugars. What appealed most was that GI intuitively made sense. We all talk about needing a sugar hit or having a sugar low, and this provided an explanation. It provided a way in to explore how foods can affect not just our physical health, but our moods as well.”
And now we know that glycemic index is a good marker for how changes in the food supply are driving an increased type 2 diabetes risk. Maybe now we can move from the narrow focus on macronutrients to a broader view of dietary quality. It looks like paying attention to this humble index might help.