The Humble Glycemic Index Marks Global Diabetes Risk

It’s been a wild ride. 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.

A Better Marker for Diabetes Risk?

This week in Nutrients, an impressive global group of nutrition scientists published a systematic review and meta analysis of glycemic index, glycemic load, and diabetes risk. Their conclusions are simple and powerful. Glycemic index and glycemic load are important markers of food quality. In fact they do an excellent job of predicting diabetes risk for individuals and for the population.

Shifting to Good Carbs

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 carbs were good, but the GI showed some carbs, 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 diabetes risk. Maybe now we can move from narrow focus on macronutrients to a broader view of dietary quality. It looks like paying attention to this humble index might help.

Click here for the paper in Nutrients and here for the latest news from the Glycemic Index Foundation.

Mixed Beans, photograph © acciarini / flickr

Subscribe by email to follow the accumulating evidence and observations that shape our view of health, obesity, and policy.

Month x, 2019