Does eating in company make you fat? A study revealed that, whether it is a dinner with friends or a family lunch, when we eat together with other people we tend to eat more. And this social action is linked, in some way, to a survival instinct that, despite having lost its function, has left its mark.

This is demonstrated by research published in The American Journal of Clinical Nutrition. Previous studies on nutrition have shown that when people eat together, the amount of food they consume increases up to 48%. The new study, coordinated by a team led by Helen Ruddock, of the University of Birmingham, in the United Kingdom, carried out a meta-analysis of 42 scientific works on eating together, confirming this hypothesis and providing a possible explanation. In ancient hunter-gatherer societies, food sharing helped the group survive periods of scarcity.

Eating together helped to ensure that all the able members of the group shared the task of gathering food, increasing collection efficiency. Furthermore, it allowed access to available food, facilitating social equity. Of course now, almost nothing remains of all this, if not a mark on our behaviour, according to which when we eat together we tend to eat as much as others.

“This leads the individual member of the group to eat more, perhaps, than would normally be the case,” the researchers conclude, “in an unconscious attempt not to lose available food resources.”