Want to live longer? Eat a little less.
At least that’s what a growing body of research suggests. A new study published Thursday showed that occasionally adopting a diet that mimics fasting could slow aging.
In the study, published in the journal Cell Metabolism, the researchers looked at the effectiveness of periodic fasting on aging-related factors in yeast, mice and humans. The results showed occasionally cutting back on calories improved health, notably in areas that worsen with age. In the mice study, the researchers had the mice consume a four-day low-calorie diet that mimics fasting (FMD) and found that it improved their metabolism, decreased bone loss, improved cognitive function, lowered cancer incidence and extended their longevity.
Humans underwent three monthly cycles of a five day diet that mimics fasting and the researchers noted a drop in risk factors related to aging, diabetes, cardiovascular disease and cancer.
The goal of the diet is to cut individuals calories down to between 34-54% of their normal consumption. For humans the diet comes out to about five days of a 750-1,050 calories per day, with very specific amounts of proteins, fats, carbohydrates, and micronutrients. “[It] looks like a low calorie plant-based diet but, in fact, [it] is designed to turn on stem cells and trigger regenerative effects and beneficial changes in many risk factors for aging and diseases,” says study author Valter Longo, director of the USC Longevity Institute.
The diet also decreased the amount of the growth hormone IGF-1 which is important for early development, but too much of it has been shown to spur faster aging.
Longo’s research is not the first to suggest occasional fasting could lead to a longer life. As TIME reported in February, several experts recommend intermittent fasting and some argue that a eating a diet with 25% fewer calories a day could lead to a longer life. Animal studies have shown promise, and human studies have shown that eating fewer calories can lower heart disease risk and impact longevity.
“I only eat a light breakfast, a full size dinner and a snack—all plant based and low proteins,” says Longo. “We believe everyone else will need to go on a diet like this more frequently. For example, someone obese with elevated fasting glucose and a family history of cancer may benefit from being on the 5-day FMD once per month.”
Longo says undergoing such a diet must be approved and supervised by a physician or registered dietitian.
Two of the study authors have equity interest in a medical food company called L-Nutra, which makes products that claim to “reduce markers associated with aging,” but neither author had a role in the data analysis.