Reduce the calories and increase that brain power!

Jan 28 2009

According to a study conducted by researchers in Germany older people benefit from a calorie restricted diet in more ways than one - they lose weight but also improve their memories.

The study found that a 30% reduction in calorie intake in older adults led to a statistically significant 20% increase in their verbal test scores - the new study suggests that cutting calories over a 3 month period may help healthy older women to retain their memory.

The study which was conducted by Dr. Agnes Floel and her colleagues at the University of Munster in Germany, included 50 women, all of whom were either normal weight or slightly overweight, with an average body mass index of 28.

Twenty of the women were assigned to the calorie-cutting group, 20 upped their intake of unsaturated fatty acids (which some studies suggest may help aging brains), and the remaining 10 stayed with their normal diet.

Care was taken to make ensure that the volunteers, despite eating a restricted diet in terms of calories, continued to eat the right amount of vitamins and other nutrients.

The researchers found that unlike the women who cut down on calories, the women who ate more unsaturated fatty acids showed no improvement in their memories, nor did those in the control group.

They say the women who cut down on calories became more sensitive to blood sugar - the regulating hormone insulin - and had a drop in the inflammation-associated molecule C-reactive protein - both these factors have been linked to an improvement in brain function.

While the findings add to growing evidence that calorie restriction can benefit health and longevity, experts say seniors who are already at a healthy weight should not contemplate dieting, as older people who do so may increase their risk of falls and fractures; they say regular exercise may achieve the same results as it has similar effects on brain function by boosting insulin sensitivity and fighting inflammation.

Experts believe that increased inflammation and a decrease in insulin sensitivity may be factors in the link between obesity and type 2 diabetes and poorer mental performance and a greater risk of Alzheimer's disease.

Research with animals over the last two decades has shown caloric restriction can extend lifespan and delay the onset of age-related disease and while some experts suggest that this latest research adds to that evidence but they say there is a fine line between undernutrition and malnutrition and such a lifestyle change is best done with professional help, rather than by some fad new diet.

There are two main theories as to how caloric restriction might slow aging - one suggests that eating less slows down the metabolism, so that the body produces fewer free radicals, which are byproducts of oxygen metabolism that can harm body tissues - while the other suggests that reducing calorie intake keeps cells under a constant low level of stress, enabling them to cope with higher levels of stress when it appears.

Dr. Floel and her colleagues are now planning larger studies of calorie restriction and mental function and will perform MRI brain scans on participants before and after they reduce their food intake in order to better understand what is happening in the brain's grey matter.

In the meantime, she says the findings offer yet another reason for people to try eating a little less as it might do something for their brain.

The study is published in the January issue of the journal Proceedings of the National Academy of Sciences.