Looking for a New Year’s resolution diet?
A new study points to one that’s been especially trendy, especially among those who hope to live long, healthy lives. Intermittent fasting, which commonly means fasting for 18 hours or more a day, can help people lose weight, live longer and fight diseases, a Johns Hopkins Medicine neuroscientist suggests in a new paper.
Published Thursday in the New England Journal of Medicine, the review article by professor Mark Mattson, Ph.D., provides evidence that the dieting tactic — which has become popular in recent years, including among locals — “could be part of a healthy lifestyle,” and even make fasters live longer, he writes.
Mattson, who has been studying intermittent fasting for 25 years and intermittently fasting himself for 20, writes that there’s increasing evidence that the tactic can provide “increased stress resistance, increased longevity and a decreased incidence of diseases, including cancer and obesity,” according to the paper, “Effects of Intermittent Fasting on Health, Aging, and Disease.”
He adds that fasting can improve blood sugar regulation and effect better suppression of both inflammation and stress. It can also benefit brain health, Mattson writes, citing previous clinical, pre-clinical and animal studies.
Mattson defines intermittent fasting diets as consisting of either having daily 6-to-8-hour eating windows, or eating only one moderate-sized meal two days out of the week (called 5:2 fasting).
By alternating the times of fasting, Mattson writes, studies have found that an ancient human adaptation for food scarcity is triggered, and cells begin converting fat into energy — a change that is not triggered by the average American diet of three meals a day, plus snacks. But, he adds, scientists still don’t “fully understand the specific mechanisms of metabolic switching,” and the diet isn’t for everyone.
Still, Mattson argues that intermittent fasting is worthy of being a part of the mainstream diet discourse.
“We are at a transition point where we could soon consider adding information about intermittent fasting to medical school curricula alongside standard advice about healthy diets and exercise,” he says.
Even for those who are open to the idea of giving up food for extended periods, there are definite side effects.
“Patients should be advised that feeling hungry and irritable is common initially and usually passes after two weeks to a month as the body and brain become accustomed to the new habit,” Mattson says, encouraging a gradual acclimation to fasting rather than going “cold turkey” with it.
Mattson hopes his paper will give better insight to physicians, who can pass that guidance on to their patients.