Can We Stop Worrying About the Glycemic Index?

For years, we've been told to avoid high-glycemic foods.  Now, a new study shows that it may not make much difference. Of course, there is a catch. Nutrition Diva explains.

Monica Reinagel, MS, LD/N, CNS
4-minute read
Episode #323

I started my career in nutrition at about the same time as people starting talking about the glycemic index. At the time, it was a fairly radical new idea: that carbohydrate-containing foods could be described according to how fast your blood sugar rises after you eat them.  

Low-glycemic carbs (sometimes referred to as “slow” carbs) are foods that cause a relatively low or slow increase in blood sugar. Low glycemic carbs include foods like non-starchy vegetables, beans, legumes, and whole grains. High-glycemic  or “fast” carbs, which include things like soda, fruit juice, refined grains, and sweets, do just the opposite. Foods that cause a quick rise in blood sugar, it was theorized, would lead to reduced insulin sensitivity, increased fat storage, and an elevated risk of Type 2 Diabetes and obesity.

See also: What Is High Glucose? 


Since then, the idea that we should limit high-glycemic foods has become completely mainstream, endorsed by everyone from the Harvard School of Public Health to the Nutrition Diva herself.

But as the years have rolled on, research on the benefits of low-glycemic diets has been surprisingly mixed. Did we all jump on the glycemic band-wagon too quickly? Does glycemic index not matter as much as we thought? Let's find out.>

The More Carbs You Eat, the More the Glycemic Index Matters

A new study adds an interesting new twist to the carbohydrate conversation—one that may help explain why low-glycemic diets don’t always produce the kind of results we think they should. In this study, researchers demonstrated that if you’re limiting the amount of carbs you eat, it doesn’t matter that much whether you choose high or low glycemic carbs. But the more carbohydrates you eat, the more important it is to choose low glycemic foods.

If you’re only having 1 or 2 servings of grains a day and you want to have white pasta or French bread, you have my blessing. 

I’ve made a similar argument before about grains: While whole grains are a more nutritious choice, portion size is more important than whether you’re eating whole grains or refined grains.

If you’re only having 1 or 2 servings of grains a day and you want to have white pasta or French bread, you have my blessing. If you’re eating 6-9 servings of grains a day, as recommended by the USDA (a recommendation that I find utterly absurd, by the way), you’d better make sure that they are low-glycemic.

See also: The Truth about Whole Grains


About the Author

Monica Reinagel, MS, LD/N, CNS

Monica Reinagel is a board-certified licensed nutritionist, author, and the creator of one of iTunes' most highly ranked health and fitness podcasts. Her advice is regularly featured on the TODAY show, Dr. Oz, NPR, and in the nation's leading newspapers, magazines, and websites. Do you have a nutrition question? Call the Nutrition Diva listener line at 443-961-6206. Your question could be featured on the show.