Lentils Outdo White Bread for Weight Loss

SYDNEY, Australia, July 18 -- Calorie for calorie, weight loss may be easier if diets are high in foods with a low glycemic index, such as lentils, according to a systematic literature review.
Low-glycemic-index foods (beans, wholegrain bread, and cereals), provide a slower, more consistent source of glucose to the bloodstream, thereby stimulating less insulin release, than foods high on the glycemic index (white bread, white rice, soft drinks), reported Diana Thomas, M.D., of the University of Sydney, and colleagues, in the July 18 issue of the Cochrane Review.
There is some evidence, Dr. Thomas said, that even when the caloric intake is the same, foods with a low glycemic index may stimulate greater weight loss in obese individuals.
Searching the Cochrane Library, Medline, Embase, Cinahl, and other sources, the reviewers analyzed six randomized controlled trials comparing low glycemic index diets with high glycemic index diets or conventional weight-loss diets.
The trials included 202 overweight or obese participants and ran from five weeks to six months, with up to six months of follow-up after the intervention ceased.
Those who were overweight and obese lost a mean of 1 kg more on the low glycemic index diets than did those on high glycemic index or conventional weight-loss diets. Total weight loss was a mean of 7 kg during the intervention period, the researchers reported.
The decreases in body mass for 163 patients (-1.1 kg, 95% confidence interval (CI) -2.0 to -0.2, P<0.05), total fat mass for 147 patients (-1.1 kg, CI -1.9 to -0.4, P<0.05), and body mass index for 48 patients (-1.3, CI -2.0 to -0.5, P<0.05) were all significantly greater in participants receiving low-glycemic-index diets compared with other weight-loss diets.
The decrease in total cholesterol was also significantly greater for low-glycemic index diets versus standard diets (-0.22 mmol/L, 95% CI -0.43 to -0.02, P<0.05), as was the change in LDL-cholesterol (-0.24 mmol/L, CI -0.44 to -0.05, P<0.05).
No study reported adverse effects, mortality, or quality-of-life data.
Satiety was not specified as an outcome measure in any of the studies. Two studies stipulated ad libitum eating (to satiety) for participants receiving the low glycemic index diet, but not for the comparison low-fat, reduced energy diet.
Only six relevant randomized trials were identified, each with methodological limitations, the researchers noted in reviewing their study's limitations.
Furthermore, a range of comparison diets was used and the duration of the interventions was short.
On the other hand, they said, the degree of overweight and obesity in the patients in these studies was wide, suggesting that the results would be applicable in other developed communities. Primary source: Cochrane LibrarySource reference: Thomas DE, et al "Low glycaemic index or low glycaemic load diets for overweight and obesity (Review)" Cochrane Library 2007: CD005105. doi: 10.1002/14651858.CD005105.pub2.