Scientists in the United States claim people who starve themselves on alternate days may live longer, boost brain power and lose weight.
The National Institutes for Aging researchers based their evidence on studies involving animals and humans.
Animals were given the bare minimum of calories needed to keep them alive. The researchers said the results showed they lived up to twice as long.
The diet was also tested on humans and appeared to protect the heart, circulatory system and brain against age-related diseases including Alzheimer's, they said.
Mark Mattson, who heads the NIA's neurosciences lab and is the neuroscience professor at John Hopkins University in Baltimore, said dietary energy restriction extended lifespan and protected the brain and cardiovascular system against age-related diseases.
"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.
One experiment involved a group of mice being fed only on alternate days, while others ate 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," The Daily Mail has reported.
"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."
Professor Mattson said that after examining the animals' brains, 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," The Mail said.