Elixir of life? Eat little and never dine too late

Experts: “Restricting food intake puts cells into ‘protection’ mode”

Eat little, in limited intervals, and never too late in the evening to live long and healthy. Starting from the teaching of Hippocrates who invited people to make food their own medicine, the experts of the Italian Society of Internal Medicine thus summarize suggestions drawn from an extensive review of the literature dedicated to the impact of nutrition on healthy longevity. Today the mechanisms of aging are known, as are the main strategies to combat it, starting right from nutrition.

One of the most important is precisely the contained diet, but still rich in all the essential nutrients. “In fact, limiting the intake of food puts the cells into ‘protection’ mode and this allows them to better resist external insults; at the same time the cells ‘on a diet’ satisfy their own needs through a sort of self-cannibalism (autophagy ) of aged and not very functional components. In practice, therefore, the caloric restriction activates a sort of ‘internal cleaning’ (such as that which is periodically done on the computer’s hard drive) which, in addition to removing deteriorated and potentially dangerous components, also stimulates cell regeneration,” the experts explain.

“From a practical point of view – explains Giorgio Sesti, president of the Italian Society of Internal Medicine – calorie restriction can be implemented according to different approaches, to be adapted to the needs of the individual and his possibilities. But it must be said that these are theoretical extrapolations than what was observed on cellular and animal models as well as on surrogate markers of healthy longevity.At the moment, in fact, for none of these approaches there is scientific proof that definitively documents their effectiveness in extending healthy life, because the results some studies in progress will only be observed in a few decades Some preliminary evidence that this also happens in humans comes from the ‘Calerie’ study recently published in Nature Aging: a 25% caloric restriction slows down the DNA methylation processes (linked to many aging processes) already after just two years”.

But food, beyond the calories, continues Sesti, “also has a high symbolic value, not to mention its ‘consoling’ effect (comfort food). And this makes it very difficult to follow a regime of strict calorie restriction for long periods of time. For this reason, scientists in the sector are looking for alternative and less penalizing methods. One of these is the selective restriction of ultra-refined foods”.

Another possible route is intermittent fasting, which is currently all the rage for weight loss. From the point of view of anti-aging calorie restriction, an effective approach could be to alternate days of almost fasting with days in which we eat in normal quantities. “The subject is at the center of many controversies (even not strictly scientific), but it is very serious. So much so that it also finds space in publications of the Nature group”, explains Sesti. Then there is the ‘way’ of the fasting-mimicking diet which consists in carrying out 5-day cycles of a low-calorie diet every 3-4 months, formulated in such a way as to reproduce the metabolic effects of fasting. This would facilitate adherence to the diet.

“Among the emerging proposals – explains Alessandro Laviano associate of Internal Medicine at Sapienza University of Rome – there is time-restricted eating. Since the first inducer of cellular activity is light, this approach suggests restricting the time window in which you can eat in less than 12 hours, preferably 8-10 hours, synchronizing it with sunlight (a sort of ‘dawn to sunset’). All this at least 5 days a week. It is known that eating late evening is associated with a greater risk of chronic-degenerative diseases, while eating ‘with natural light’ seems to reduce the inflammatory state and could facilitate weight loss”. However, concludes Sesti, “modifying one’s diet and body weight can also negatively influence one’s biological age”. For this reason, these strategies, especially the more experimental ones, must always be adopted on the advice of the doctor and monitored by him.