Low glycemic index diets for the management of type 2 diabetes

This study investigated the effectiveness of low-glycemic index (GI) diets in patients with type 2 diabetes. The authors concluded that the low-glycemic index diets are more effective in controlling blood sugar levels compared to high-glycemic index or other diets in these patients.

In addition to physical exercise, the glycemic index (GI) has been recommended as a dietary guide to help patients with type 2 diabetes better manage their blood sugar levels. The GI value of a given food is a measure of how quickly the carbohydrates in it are digested compared to glucose. High GI foods like white bread have carbohydrates that are digested quickly, leading to quick spikes in blood sugar. Low GI foods like legumes, lentils, and oats have carbohydrates that are digested slowly, leading to slower rises in blood sugar.

Low-GI diets have been proposed as a way to manage blood sugar levels in patients with type 2 diabetes.

This study analyzed the results of six studies to determine the effectiveness of low-GI diets compared to high-GI or control diets. Control diets included high-cereal fiber, high-wheat fiber, the standard diabetes diet, and the conventional carbohydrate exchange diet. These studies ranged from 2 weeks to 22 months in length.

Overall, compared to the control diets, the low GI diet significantly reduced HbA1c (average blood glucose over 3 months) and fasting blood sugar (average blood glucose after 8 hours of fasting).

In two studies, the low GI diet significantly improved HbA1c levels compared to the control diets. In one study, HbA1c levels decreased by 0.5% (low GI diet) compared to 0.18% (high cereal fiber diet). In another study, HbA1c levels decreased by 0.5% (low GI legume diet) compared to 0.3% (high wheat fiber diet). 

Four studies reported improved fasting blood sugar levels with the low-GI diet compared to the high GI and control diets, though not all were statistically significant.

This study concluded that low-glycemic index diets led to greater improvements in HbA1c and fasting blood sugar levels compared to high-glycemic index or control diets in patients with type 2 diabetes.

The number of studies analyzed here was quite small, and the studies also had small sample sizes. The results of the current analysis need to be further confirmed in a larger analysis that includes more studies.

If you have type 2 diabetes, talk to your doctor about adjusting the glycemic index of your diet to improve your blood sugar levels.