Researchers at the University of Southern California developed a new diet called "five-day fasting," which is not only beneficial for weight loss, but also for extending lifespan and lowering one's risk on cancer and diabetes.
The team tested the diet on old mice for four days to mimic the effects of fasting. They observed a decrease on the visceral belly fat and an increase on the progenitor and stem cells in most organs of old mice, including the brain. The subjects also lived longer, had reduced cancer and diabetes risk, developed a stronger immune system and improved their mental health.
The researchers decided to test the diet on humans. They recruited 19 participants who underwent a five-day fasting diet once a month for three months. The participants reduced their calorie intake to almost half of the normal during the fasting period. They were asked to go back to their regular eating habits after fasting.
After the follow-up period, the researchers found that the biomarkers and risk factors for aging, diabetes, cancer, and heart disease were reduced, similar to their observation on the mice.
"Strict fasting is hard for people to stick to, and it can also be dangerous, so we developed a complex diet that triggers the same effects in the body," Valter Longo, Edna M. Jones Professor of Biogerontology at the USC Davis School of Gerontology and director of the USC Longevity Institute, said in the university news release. "I've personally tried both, and the fasting mimicking diet is a lot easier and also a lot safer."
Longo added that the five-day fasting diet is beneficial to those who want to lose weight but are worried about the adverse side effects.
However, the researchers warned those who would like to try the five-day fasting diet to consult their doctors first. It is also not advisable to diabetes patients
"Not everyone is healthy enough to fast for five days, and the health consequences can be severe for a few who do it improperly," Longo said. "Water-only fasting should only be done in a specialized clinic. Also, certain types of very low calorie diets, and particularly those with high protein content, can increase the incidence of gallstones in women at risk."
The study was published in the June 18 issue of the journal Cell Metabolism.
