Friends, No Friends Both Lead To Obesity

A new study purports to show that kids eat more when they're with their friends. But another study found that "social stress" caused monkeys to gain dangerous visceral fat. So do friends make us fat or not?

In the first study, kids were paired with either a friend or a stranger and told to eat as much as they wanted. Both overweight and "normal" weight kids ate more with a friend, but overweight kids ate more if their partners were overweight, whether they knew them or not. ScienceDaily says the study "demonstrates that friends may act as 'permission givers' on children's food intake." And study author Sarah Salvy says,

Overweight children are more likely to find food more reinforcing than non-overweight youth. Being in the company of overweight peers may give them the permission to eat more or may decrease their inhibitions, increasing what are seen as the norms of appropriate eating, or how much one should eat.

The study doesn't appear to address whether overweight children actually "find food more reinforcing," but it does manage to moralize eating by talking about it in terms of "permission." It's not odd that kids felt more comfortable eating with a friend than with a stranger, but it's interesting that coverage of the study implies that the higher intake is the disordered one. Isn't it possible that kids consciously or unconsciously eat less than they normally would when they're with a stranger, because they're uncomfortable? And isn't it also possible that overweight kids eat less with a skinnier partner because they're embarrassed about being heavier? As someone who loses my appetite when I'm stressed, I've relied on friends to cook with me and encourage me to eat during difficult times, and I have to object to the notion that eating more at a shared meal is a bad thing.

The second study examined groups of monkeys, and found that the ones who were lower in the social hierarchy — who "are often the target of aggression and aren't included in group grooming sessions as often as dominant monkeys" — gained more visceral fat, or fat in the abdominal cavity. This type of fat contributes to atherosclerosis and heart disease. In women and female monkeys, hormones can protect against these conditions, but researchers also found that monkeys with more visceral fat had lower levels of protective hormones. Study author Carol A. Shively wisely points out that "obesity is directly related to lower socioeconomic status in Western societies, as is heart disease. So, the people who have fewer resources to buffer themselves from the stresses of life are more likely to experience such health problems."

Not only do people of lower socioeconomic status have fewer material resources to cope with stress, they may also have more "social stress" as a result of being lower in the economic hierarchy. And perhaps there's a feedback loop here, in which overweight people are socially stigmatized, causing them to build up more visceral fat and increase their risk of heart disease. Visceral fat is much more dangerous than fat in other areas of the body, and the stress of being overweight in a sizeist society might cause people who don't have a lot of this type of fat (not all overweight people do; not all skinny people don't) to develop it.

So might some of the vaunted health risks of obesity actually be the result of stigma? It's possible. It would be interesting to see how overweight people fare health-wise in societies that don't look down on them (although some of these societies, like Mauritania, have their own problems). Failing that, scientists could take a more nuanced look at childhood social influences, rather than telling us that eating with friends makes kids fat.

Friendship Influences Eating Behavior, Particularly When Friends Are Overweight [ScienceDaily]
Overweight Friends Alter Eating Patterns, Study Shows [Softpedia]
New Research Links Social Stress To Harmful Fat Deposits, Heart Disease [EurekAlert]