When people eat together with other acquaintances or close friends, as in a family meal or eating with friends, they tend to eat more. This is called ‘social facilitation’ and is possibly traceable all the way back to basic human behavior, allowing people to survive better. The current analysis was published in The American Journal of Clinical Nutrition on 21 August 2019.
Prior research has shown that when people eat together, the amount of food they eat goes up by as much as 48% in some cases. Similarly, in a study on obese women, the amount of food eaten was about 30% higher when they ate socially, compared to eating alone. The longer duration of feeding that is typical with a shared meal, as well as the fact that in such a setting one is expected to eat, may also have a small influence on the increase in individual food intake at this time compared to eating alone.
The research that found this effect on food intake was carried out in the UK and Australia, and consisted of a meta-analysis of 42 studies of social eating.
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Why do we eat more together?
The explanation that these scientists have come up with is that in hunter-gatherer societies, sharing food helped the group survive periods of scarcity, leading to a pattern which presumably survives even today. Eating together also helped ensure that all able-bodied members shared the task of getting food together, increasing the efficiency of food-gathering. In addition, all members had equal access to the food available, facilitating social equity.
The benefits of eating together include:
- Increased enjoyment and feeling of reward which motivates continued consumption of food
- Socially, overeating is okay when it’s done in company, but not in private
- Hospitality in the form of providing food for a company of people is an act associated with social praise and appreciation which makes for a stronger social relationship between the host and the guests
Does it work when eating with strangers?
It is clear from the study that this type of social facilitation doesn’t occur when food is eaten by people in a common place but without a setting of friendship or closeness. This could be because of the universal desire to impress strangers favorably, one manifestation of which could be selecting smaller food portions. Some of the research tends to show that this selection of smaller-than-desired portions is more important as a moderating factor when it comes to women eating with men who they wish to make a good impression on, or when people with excessive body weight are eating in public and want to avoid criticism for overeating. This would obviously be of greater weight when eating with strangers than with people whom one already knows and trusts.
In the present scenario, many societies now have plentiful food resources, leading to a mismatch between this inherited pattern of eating together and the outcome, which is now potentially harmful rather than beneficial. In other words, eating with friends or family no longer is required to ensure a fair and equal distribution of food, given the relative abundance of food in today’s world. Instead, it is now a powerful factor in perpetuating or promoting unhealthy intakes of food nutrients.
Many animals also show the same pattern, such as gerbils, rats and chickens, suggesting that social facilitation of feeding has a purpose behind it. There is a more or less fierce competition for resources between individuals. In such a setting, if one person eats more than the others, it is likely to lead to exclusion from the whole group, an act which jeopardizes food security. At the same time, individuals also want to be recognized as food providers, or as those who unselfishly share their food. This creates a tug-of-war with the equally or more important need to get as much food as is necessary.
As a result of this tension, when eating together everyone tends to eat as much as others do – a match of behavior. This leads to the individual member of the group eating more, perhaps, than would be typically the case, in an unconscious effort to not miss out on the available food resource.
Researcher Helen Ruddock says, “What we describe as 'social facilitation' can be seen as a natural by-product of social food sharing - a strategy that would have served a critical function in our ancestral environments. This also explains why it is more likely to occur in groups with individuals who are familiar with each other.”
A systematic review and meta-analysis of the social facilitation of eating. Helen K Ruddock, Jeffrey M Brunstrom, Lenny R Vartanian, & Suzanne Higgs. The American Journal of Clinical Nutrition, Volume 110, Issue 4, October 2019, Pages 842–861. https://doi.org/10.1093/ajcn/nqz155. https://academic.oup.com/ajcn/article-abstract/110/4/842/5552759/?redirectedFrom=fulltext