Low-glycemic carbs fit into a healthy diet. (Creative Commons/Flickr)

Dr. David Ludwig of the New Balance Foundation Obesity Prevention Center at Boston Children’s Hospital published a 4-week study examining weight loss results between low-fat, low-carbohydrate and low-glycemic diets in obese adults ages 18-35.

“The low-carb diet was the clear winner. The low-fat diet was the loser. But it was the diet in the middle, the low-glycemic index diet, that Ludwig suggests is more promising. It burned more calories per day than the low-fat diet and proved easier to stick to over the long term than the low-carb diet,” according to NPR.org. 

Low-gylcemic foods such as grains, vegetables, oatmeal, fruits and beans are digested slowly, which keeps dieters full longer because glucose is released gradually. After eating carbohydrates, a chemical reaction involving glucose occurs and releases the hormones insulin and glycogen. When dieters eat high-glycemic carbohydrates, such as baked goods, their blood sugar spikes very quickly followed by a crash, telling their body they’re hungry again. Therefore, low-glycemic dieters eat fewer calories and loose weight because they are satisfied longer and don’t have a rapid blood sugar change.

"Eating “good” carbs—bran cereal and many fruits and veggies, like apples and carrots, for example—controls appetite and delays hunger, promoting weight loss. “Bad” carbs, like white bread and instant mashed potatoes, are quickly digested and released into the bloodstream, spiking blood sugar and making you hungry sooner," according to U.S. News. 

The University of Sydney has an online glycemic index database and includes recipes and meal plans to help dieters who want to go low-glycemic, such as people with diabetes who need to control blood sugar levels and those struggling with obesity. Foods are scored between zero and 100 to determine if they are high-, medium- or low-glycemic. For example foods with scores higher than 70 such as white rice and bread are high-glycemic, and foods ranked 55 or lower, such as carrots and apples, are low-glycemic.

Some experts don’t recommend the low-glycemic approach to weight loss because the index can be misleading. "It's difficult to identify the GI value of a meal. Meanwhile, some foods with a low GI value are also packed with fat and/or salt and contain few nutrients. Chocolate and crisps, for example, are high in fat and contain few vitamins and minerals," according to an online UK diet site.

“Using the GI to lose weight is unnecessarily complicated, and it does not simplify the task of choosing healthier food to lose weight or manage blood sugar," said Hope Warshaw to WebMD, MMSc, RD, a certified diabetes educator and author of books about diabetes including Diabetes Meal Planning Made Easy.

Although the low-glycemic approach may work for some, not everyone will experience long-term weight loss. “Food is not one-size-fits-all,” said nutrition consultant, Robyn Flipse, MS, RD.

FitGirl is a weekly health and fitness column. If you have any questions you want to see answered feel free to email me.