Low fat, high carb diet linked to better moods

Researchers from Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO), University of South Australia, and Flinders University examined 106 overweight or obese adults, with an average age of 50.

The subjects were randomly assigned to two groups; one group was put on low fat, high carbohydrate diet including bread, pasta, rice, and the other one was put on high fat, low carbohydrate diet with more meat and dairy products for one year each.

The daily intake of calories was restricted to 1,433 to 1,672 in both the diet programmes.

In order to evaluate their mood, the volunteers were given three questionnaires which measured various aspects of mood, including tension-anxiety, depression-dejection and anger-hostility.

Those on low fat, high carb diet exhibited better mood
Findings of the study published in the Archives of Internal Medicine suggest those put on low fat and high carb diet displayed better moods and were found to be less angry, hostile or depressed after the first eight weeks compared to others who remained on high-fat and low carb diet.

After a year, the mood improvements lasted only in the low fat diet group, while those in high fat group reverted back to their previous moods.

However, both the dietary programmes were found to be equally effective in achieving the weight loss—up to 30 pounds (13.7 Kg)--for each individual in both the groups.

The researchers explained that high carbohydrates are associated with increasing serotonin--neurotransmitter in the brain involved in mood concentrations in the brain.

"Over one year, there was a favourable effect of an energy-restricted (low-fat) diet compared with an isocaloric (low-carb) diet on mood state in overweight and obese individuals," researchers said.

"The exact mechanism for the observed effects on mood still remains largely unknown. However, if the mechanism for the return of mood toward more negative baseline levels following weight loss with a very low-carbohydrate diet is related to this diet being so far removed from normal dietary habits, then a very low-carbohydrate diet may be best recommended for individuals who habitually consume low amounts of carbohydrate foods in their diet," said lead researcher Grant D. Brinkworth.

Brinkworth is a research scientist with the food and nutritional sciences division of the Commonwealth Scientific and Industrial Research Organisation in Adelaide, Australia.

Previous studies have also shown that a low fat, high carb diet is linked with overall psychological well being.