BETHANY, Mo. – People looking to lose weight or eat healthier have sought to reduce calories, carbs and fats in their diets. In recent years, health-conscious consumers have been seeking out foods with a low glycemic index. But how effective is this for managing health?

“The glycemic index is used with foods that contain carbohydrates,” says Janet Hackert, regional nutrition and health education specialist for University of Missouri Extension. It measures how quickly consumed food raises blood glucose levels. Glucose, a sugar, is the fuel the human body uses for energy.

A glycemic index (GI) of 70 or above out of 100 is considered high, while 55 or below is considered low. “A food’s GI rating is very complex, based on a number of variables, including what other foods are eaten with it,” Hackert says.

High glycemic index foods may be useful for athletes who need a quick energy source, she says. Low glycemic index foods may help moderate glucose and energy release over time. People with diabetes have used this system of identifying foods to better control their blood glucose levels, avoiding dangerous highs or lows.

“Although these numbers may help us make healthier choices, it may not be quite so straightforward as only eating foods within a certain glycemic index range,” Hackert says.

According to the American Diabetes Association, studies suggest that different types of carbohydrates differ in their effects on blood glucose, and that the total amount of carbohydrates eaten predicts blood glucose response better than glycemic index. “So portion size may be an important aspect of a healthy eating plan—for someone with diabetes or for anyone,” she says.

In addition, a recent study reveals that the glycemic index for a given food can vary from person to person, and can differ based on a variety of factors, including freshness, amount of processing, cooking method, variety (such as short-grain rice compared to long-grain varieties) and what other foods you are eating with it.

“The bottom line is to find a healthy eating pattern that incorporates a variety of carbohydrate sources, including whole grains, nuts, legumes, fruits and non-starchy vegetables,” Hackert says. “Choosing nutritious foods from all the food groups provides not only needed carbohydrates, including fiber, but also the wide range of other nutrients a person needs to be healthy.”

For more food and nutrition information from MU Extension, including feature articles, answers to frequently asked questions and learning opportunities, go to www.missourifamilies.org/nutrition.