This article is taken from the monthly Sciences et Avenir – La Recherche n°904, dated June 2022.
Eat better to live longer? What if we had to eat less above all? In any case, this is what a study by Yale University (New Haven, United States) suggests. Published in February, it is the first to demonstrate the positive effects of calorie restriction in humans. Until now, the method had only shown its effectiveness on animals. And still little ones: flies, mice or worms. Or species whose existences are short enough to be studied in their entirety in the laboratory. In these animals, reducing the quantity of calories ingested makes it possible to increase life expectancy. Sometimes very significantly: 50% more life for certain primates such as mouse lemurs. Spectacular results are also obtained if animals are fed at specific times of the day and not at other times. (read box below).
But other experiments, still in mice, had shown that calorie restriction increased infections. Unable to conduct studies over several years with many human participants, the American team led by Vishwa Deep Dixit, director of the Center for Research on Aging at Yale, attempted an experiment with 200 volunteers. Half of them did not have to change anything in their eating habits. The hundred others had to reduce their calorie intake by an average of 14%. All the participants had to carefully note their menus, the quantity of what they ingested, for two years.