Low Glycemic Index Diet Might Not Benefit Heart Disease, Diabetes Risk

A low glycemic index diet does not improve heart disease or diabetes risk factors, according to a new study.

The glycemic index is a numerical index that ranks carbohydrates based on their rate of glycemic response (i.e. their conversion to glucose within the human body). Glycemic index uses a scale of 0 to 100, with higher values given to foods that cause the most rapid rise in blood sugar. Pure glucose serves as a reference point and is given a glycemic index (GI) of 100. Foods with a high GI are those that are rapidly digested and absorbed and result in marked fluctuations in blood sugar levels. Low-GI foods, by virtue of their slow digestion and absorption, produce gradual rises in blood sugar and insulin levels.

In a recent study, 163 overweight adults were randomly assigned to one of four complete diets. Each diet lasted for 5 weeks, and each participant was assigned to at least two study diets. The first diet was a high-glycemic index, high-carbohydrate diet. The second diet was a low-glycemic index, high-carbohydrate diet. The third diet was a high-glycemic index, low-carbohydrate diet. Finally, the fourth diet was a low-glycemic index, low-carbohydrate diet. All diets were based on the Dietary Approaches to Stop Hypertension (DASH) diet. The major outcome measures included insulin sensitivity, low-density lipoprotein (LDL or “bad”) cholesterol, high-density lipoprotein (HDL or “good”) cholesterol, triglyceride levels, and blood pressure.

The researchers found that maintaining a low-glycemic index diet did no improve insulin sensitivity, blood pressure or cholesterol levels, with only reductions in triglycerides when comparing the high-glycemic index, high carbohydrate diet to the low-glycemic index, low-carbohydrate diet.

The authors concluded that using the glycemic index to select foods for the DASH diet does not reduce heart disease or diabetes risk factors. Additional research is warranted.

For information about the low glycemic index diet, please visit Natural Standard’s Health & Wellness.

References

1. Natural Standard: The Authority on Integrative Medicine.
2. Sacks FM, Carey VJ, Anderson CA, et al. Effects of high vs low glycemic index of dietary carbohydrate on cardiovascular disease risk factors and insulin sensitivity: the OmniCarb randomized clinical trial. JAMA. 2014 Dec 17;312(23):2531-41.