Thursday, October 11, 2007

Low glycemic weight loss myth refuted

whole-grain bread
Yet another weight loss myth does not stand scientific scrutiny; you will not lose any weight by switching to foods with a low glycemic index. This index measures the relative speed of sugar uptake into the blood stream, compared to glucose which has a glycemic index (GI) of 100. Foods with a high GI challenge the body's control of blood sugar level, triggering a high production of insulin. A constantly high load of insulin may blunt the body's sensitivity to this hormone which is considered a first stage of diabetes. Thus, foods with a low glycemic index are considered healthier because they make it more easy for the body to maintain blood sugar balance.

While this is no question, the weight loss promoters have taken over the issue, claiming that low GI food may be helpful to curb the appetite and to lose weight. Nope, they are wrong, as a study about reduced glycemic index on satiety, energy intake and body weight has shown recently.

Research details: Nineteen women with a body mass index between 24 and 47 have been under two kinds of controlled diets for twelve weeks each. One diet had a GI of 56, the other 64. During both diet periods, the appetite, satiety, energy intake and weight remained unchanged. Conclusion of the authors:

"This study provides no evidence to support an effect of a reduced GI diet on satiety, energy intake or body weight in overweight/obese women. Claims that the GI of the diet per se may have specific effects on body weight may therefore be misleading."
Given the small number of test subjects and the small GI difference of 8, one might argue that a really extreme diet in a great number of persons may show an effect. But such a scenario sounds like being far from reality. Plus it is a fact that most weight loss methods have failed due to the body's self-regulation of weight under restricted food conditions.

Photo credit: flickr.com/photos/jow/45849736/

No comments: