Low-glycemic diet drops weight, cholesterol
Maybe there is a new and better way to get your patients to lose weight. A review of six studies comparing low-glycemic index (LGI) diets with conventional weight-loss plans showed LGI dieters outpaced the control groups on several key measures:
• Body mass: weighted mean difference -1.1 kg vs. -0.2 kg
• Total fat mass: -1.1 kg vs. -0.4 kg
• BMI: -1.3 vs. -0.5
• Total cholesterol: -0.22 mmol/L vs. -0.02 mmol/L
• LDL cholesterol: -0.24 mmol/L vs. -0.05 mmol/L
In studies that compared informal LGI diets with structured conventional plans, LGI dieters fared “even better, even though they could eat as much as desired.”
All 202 participants in these studies were overweight (BMI 25-30) or obese (BMI ≥30). None was diabetic. Durations on the diets ranged from five weeks to six months, with up to six months of follow-up (Cochrane Database Syst Rev. 2007;3:CD005105). “Lowering the glycemic load of the diet appears to promote weight loss and improve lipid profiles and can be simply incorporated into a person’s lifestyle,” conclude Diana Thomas, MD, of The University of Sydney (Australia) and her colleagues.
The finding is particularly significant for diabetics. “Obesity is the most frequent risk factor for type 2 diabetes,” the researchers point out. “Glycemic control is crucial to reduce complications of disease, improve the quality and duration of life, and minimize the need for expensive health care.”
Foods that have a high glycemic index are often simple carbohydrates that will increase blood sugar levels quickly. Examples include white bread, potatoes, soft drinks, ice cream, and candy. LGI foods—such as cereals based on wheat bran, oats, or barley; whole-grain breads; fruit; lentils; and beans—are harder to digest. They affect blood sugar more slowly, flattening fluctuations in blood glucose levels.
But according to the Healthy Weight Forum Web site (www.healthyweightforum.org), merely giving patients a list of LGI foods may not be sufficient. Individual glycemic responses to food vary with many factors, including age, metabolism, time of day, and how the food was cooked. The site suggests people monitor how different foods affect them. For more on the effect of LGI foods, see “A new method to save eyesight” on page 23.