Low GI Diet Reduces Inflammation

SEATTLEOverweight and obese adults who consume a diet rich in slowly digested carbohydrates, such as whole grains, legumes and other high-fiber foods, significantly reduces markers of inflammation associated with chronic disease, according to a new study published in the Journal of Nutrition. The findings also suggest a low-glycemic diet, which does not cause blood-glucose levels to spike, also increases a hormone that helps regulate the metabolism of fat and sugar.

This finding is important and clinically useful since C-reactive protein is associated with an increased risk for many cancers as well as cardiovascular disease," the researchers said. Lowering inflammatory factors is important for reducing a broad range of health risks. Showing that a low-glycemic-load diet can improve health is important for the millions of Americans who are overweight or obese."

Researchers at the Fred Hutchinson Cancer Research Center conducted a controlled, randomized feeding study, which involved 80 healthy Seattle-area men and womenhalf of normal weight and half overweight or obese. Among overweight and obese study participants, a low-glycemic-load diet reduced a biomarker of inflammation called C-reactive protein by approximately 22%.

Study participants completed two 28-day feeding periods in random orderone featuring high-glycemic-load carbohydrates, which typically are low-fiber, highly processed carbs such as white sugar, fruit in canned syrup and white flour; and the other featuring low-glycemic-load carbohydrates, which are typically higher in fiber, such as whole-grain breads and cereals. The diets were identical in carbohydrate content, calories and macronutrients. All food was provided by the Hutchinson Centers Human Nutrition Laboratory, and study participants maintained weight and physical activity throughout.

The found among overweight and obese study participants, a low-glycemic-load diet increased blood levels of a protein hormone called adiponectin by about 5%. Adiponectin plays a key role in protecting against several cancers, including breast cancer, as well as metabolic disorders such as type2 diabetes, nonalcoholic fatty liver disease and hardening of the arteries.

The bottom line is that when it comes to reducing markers of chronic-disease risk, not all carbohydrates are created equal. Quality matters," the researchers said.

The researchers suggested simple dietary changes such as choosing carbohydrates that are less likely to cause rapid spikes in blood glucose, including whole grains; legumes such as kidney beans, soy beans, pinto beans and lentils; milk; and fruits such as apples, oranges, grapefruit and pears.