030167 Are Burgers, Fries and Kebabs Addictive?

London - A steady diet of hamburgers, fries and foods high in fat and loaded with calories may not only pile on the pounds -- some scientists are questioning whether it could be addictive.

Researchers who have been testing the biological effects of fast foods are discovering that they can trigger hormonal changes in the body which could make it difficult to control eating.

"New and potentially explosive findings on the biological effects of fast food suggest that eating yourself into obesity isn't simply down to a lack of self-control," New Scientist magazine said.

Fast food meals can deliver nearly the recommended daily calorie and fat intake in one meal. As people put on weight, they become more resistant to the hormone leptin, which is strongly linked to weight and appetite, and a brain peptide called galanin that stimulates eating.

Leptin releases signals to the part of the brain that co-ordinates eating behaviour but as people gain weight they become more resistant to the effects of the hormone.

"Their brain loses its ability to respond to these hormones as body fat increases," Michael Schwatz, an endocrinologist at the University of Washington in Seattle, told the magazine.

Animal studies by Sarah Leibowitz, at Rockefeller University in New York, have also shown that young rats fed a high fat diet early in life grew up to be obese adults.

Researchers are also looking into whether bingeing on foods high in fat and sugar cause changes in the brain associated with addiction to drugs.

"Highly palatable foods and highly potent sexual stimuli are the only stimuli capable of activating the dopamine system with anywhere near the potency of addictive drugs," according to John Hoebel, a psychologist at Princeton University in New Jersey.

But the magazine said other scientists argue there is no conclusive evidence that foods high in fat and sugar are addictive.

"Considering the paucity of evidence that fast food is addictive, I think the burden is on advocates of the addiction argument to provide evidence of addictiveness," said Michael Jacobson of the Centre for Science in the Pubic Interest, a lobby group in Washington.

RETURN TO HOME PAGE

E-mail: sflanagan@sprintmail.com