Washington, April 19 : A study of mice has shown that changing to diets low in fat or carbohydrates may cause anxiety and increase stress levels.

The researchers acclimated mice to either high-fat (HF) or high-carbohydrate (HC) diets by using a variety of standard measures of mouse behaviour, and observed behavioural changes in the animal. They also examined the brains of the mice for increases in corticotrophin releasing factor (CRF) levels that can indicate high stress levels.

“Our behavioural, physiologic, biochemical, and molecular analyses support the hypothesis that preferred diets act as natural rewards and that withdrawal from such a diet can produce a heightened emotional state,” Dr. Tracy L. Bale writes.

The study, published in Biological Psychiatry, shows that once deprived of their preferred diet, the mice would overcome their natural aversion to bright environments to obtain the high-fat foods, even when standard food was available.

“These results strongly support the hypothesis that an elevated emotional state produced after preferred-diet reduction provides sufficient drive to obtain a more preferred food in the face of aversive conditions, despite availability of alternative calories in the safer environment,” write authors.

Our results may suggest that, similar to the case of an individual who is in withdrawal from a rewarding substance, these mice effectively are displaying risk-taking behavior to obtain a highly desirable substance, supporting the powerful rewarding aspects of the HF food,” they add.

The new findings may be important for researchers who have been studying factors that contribute to dieting failures in most of the people who switch over to food less in fat or carbohydrates in order to reduce their weight. (ANI)