According to a team from the National Institute on Ageing in Baltimore, America, fasting for one or two days a week may protect against Alzheimer’s, Parkinson’s and other degenerative brain conditions.

Prof Mark Mattson, head of the laboratory of neurosciences at the NIA and professor of neuroscience at John Hopkins University in Baltimore, said, “Reducing your calorie intake could help your brain, but doing so by cutting your intake of food is not likely to be the best method of triggering this protection. “It is likely to be better to go on intermittent bouts of fasting, in which you eat hardly anything at all, and then have periods when you eat as much as you want.” Cutting daily food intake to around 500 calories – which amounts to little more than a few vegetables and some tea – for two days out of seven had clear beneficial effects in their studies, claimed Mattson.

The National Institutes for Aging said their research was based on giving animals the bare minimum of calories required to keep them alive and results showed they lived up to twice as long. Professor Mattson said he found the mice fed on alternate days were more sensitive to insulin and needed to produce less of it. High levels of the hormone, which is produced to control sugar levels after a meal or snack, are usually associated with lower brain power and are at a higher risk of diabetes.

The brains from both sets of rodents were then examined and Professor Mattson said he found the calorie restricted diets appeared to improve the function of brain synapses. These are the junctions between brain cells which promote the generation of new cells and make them more resistant to stress.

“Dietary energy restriction extends lifespan and protects the brain and cardiovascular system against age-related disease,” said Mattson