Starving yourself on alternate days can make you live longer, according to scientists.
A group of Americans have said that fasting on and off can boost brain power and help to lose weight at the same time.
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.
The diet has since been tested on humans and appears to protect the heart, circulatory system and brain against age-related diseases like Alzheimer's.
'Dietery energy restriction extends lifespan and protects the brain and cardiovascular system against age-related disease,' said Mark Mattson, head of the laboratory of neurosciences at the NIA and professor of neuroscience at John Hopkins University in Baltimore.
'We have found that dietary energy restriction, particularly when administered in intermittent bouts of major caloric restriction, such as alternative day fasting, activates cellular stress response pathways in neurones,' he said to the Sunday Times.
In one set of experiments, a group of mice were only fed on alternate days while others were allowed to eat daily.
Both groups were given unlimited access to food on the days they were allowed to eat and eventually consumed the same amount of calories.
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.
Previous research has found that starving yourself for a few days can help in the fight against cancer.
Scientists found that depriving healthy cells of the food they need sends them into a survival mode, making them highly resistant to stress and damage caused from chemotherapy.
Experts have described the behaviour similar to animals waiting out the winter by hibernating.