Apparently, Obesity is Contagious

[General Zod]

As opposed to people eating too much.

Obesity 'contagious', experts say
obesity
The study looked at data collected over 32 years
Having a friend, sibling or spouse who is overweight raises a person's risk of being obese too, US researchers say.

They said data on more than 12,000 people suggested the risk was increased by 57% if a friend was obese, by 40% if a sibling was and 37% if a spouse was.

They argued this showed social factors, such as the body sizes of other people, were important in developing obesity.

Experts said the New England Journal of Medicine study was not conclusive as other hidden factors could be to blame.


People come to think that it is OK to be bigger since those around them are bigger
Professor Nicholas Christakis

Researchers at Harvard Medical School and the University of California, in San Diego, looked at data collected over 32 years as part of a heart study.

Participants gave personal information, including their body mass index, and the names of friends who could be contacted.

'Causal relationship'

The authors were able to map social connections including both friends and family members.

The effects were generally larger between people of the same sex.

And their analysis suggested that the links could not be solely attributed to similarities in lifestyle and environment, for example the impact of friends existed even where friends lived in different regions.


The statistics may be meaningful, but in real life this is not very helpful to people who are overweight
Professor Andrew Hill

Author Professor Nicholas Christakis said: "It's not that obese or non-obese people simply find other similar people to hang out with.

"Rather, there is a direct, causal relationship. What appears to be happening is that a person becoming obese most likely causes a change of norms about what counts as an appropriate body size.

"People come to think that it is OK to be bigger since those around them are bigger, and this sensibility spreads."

Moral support

Dr Richard Suzman, director of the National Institute of Aging's Behavioral and Social Research Programme, said the finding could have important implications.

He said: "This seminal study breaks important new ground in showing how social networks may amplify other factors and help account for the dramatic increase in obesity across the [US] population."

Dr Ian Campbell, medical director of charity Weight Concern, said it was no surprise that people who are obese tended to be friends with others who were obese, but that the fact that the link was more important between friends than siblings was "very interesting".

He said this suggested that social factors were even more important than physical ones in obesity.

He added that, on the positive side, if overweight people had friends who were obese, they could offer moral support to help each other lose weight.

'Speculation'

But Professor Andrew Hill, of the University of Leeds, said it was purely speculation to suggest that people's body images change because their friends become obese.

And he said it was important not to forget things which are known as key factors in obesity, such as diet and exercise.

"The statistics may be meaningful, but in real life this is not very helpful to people who are overweight.

"We don't have an understanding of what is really causing the relationship - it might be very complicated."

about sums up my reaction.

[PeZook]

There's some truth to it. When you associate with people, you tend to pick up some of their habits. Pick up enough bad food or excercise habits, and you gain weight.

It's the same with people who know criminals being arrested sometimes. Though it only counts if your obsesity problem is behavioral, rather than physiological, though IIRC it's purely behavioral in most people.

[Surlethe]

There's some truth to it. When you associate with people, you tend to pick up some of their habits. Pick up enough bad food or excercise habits, and you gain weight.

I was listening to this on NPR yesterday; they pointed out that obesity is contagious even if the obese friend lives hundreds of miles away. This doesn't discount habit exchange as a mechanism, but it does cast some doubt on it.

And if habits are contagious, then is fitness contagious, too?

[PeZook]

I was listening to this on NPR yesterday; they pointed out that obesity is contagious even if the obese friend lives hundreds of miles away. This doesn't discount habit exchange as a mechanism, but it does cast some doubt on it.

Hmm, the OP article does mention a psychological "comfort" mechanism that helps this. It may be a complex issue involving both mechanisms. Further studies on the mater would be excellent to have.

And if habits are contagious, then is fitness contagious, too?

I can't see why not. Probably not as much, though - getting "infected" with obesity literally requires you to do nothing. Laziness may make you ridicule the "fitness freak" instead of joining in. The outcome would probably depend on several factors, like the magnitude of friendship.

[Spin Echo]

The use of the word "contagious" is misleading. Nowhere in the study do the authors use it. It would be like refering to bell bottoms or mullets as contagious. You don't "catch" a mullet, but if many people around you have them, you begin to see them as a socially acceptable haircut.

And if habits are contagious, then is fitness contagious, too?

I'd imagine so. If you're part of a social group that sees excerise as important, you'd be less likely to think it's okay to sit on your arse and watch TV all day. Even if you don't see them often, if you consider yourself one of "them", you'd still want to behave like them.

Of course, that strikes me more of peer pressure "Everyone else is in good shape so I need to be in good shape too" whereas the obesity seems a bit more of a mob mentality "Everyone else has put on weight so it's no big deal if I do too". Perhaps I'm just splitting semantic hairs here, though.

[Darth Wong]

It's more than just peer pressure. The types of food that are available in restaurants and grocery stores is different if you life in an area rife with obesity. That doesn't make it impossible to stay thin, of course, but it creates an extra hurdle.

I knew a young woman from the Bahamas who spent a lot of time in the southern US before moving to Toronto. At first she complained that she couldn't get any decent food. Everything was light and (to her way of thinking) tasteless because she was used to an almost completely deep-fried diet. After she'd been here for six months, she lost something like 20 or 30 pounds and she was starting to love the local food.

[Spoonist]

It's not that obese or non-obese people simply find other similar people to hang out with.

My gut instinct would be counter to this. Its rare to see obese-fit friendships, while obese-obese and fit-fit friendships are everywhere.
Its also an observation that kids on fat-camps become fast friends, but then friendships end depending on if you lose or gain weight.

looked at data collected over 32 years as part of a heart study. Participants gave personal information, including their body mass index, and the names of friends who could be contacted.

Either the article writer messed this up or this is weighted [pun] data. It should be followed up with a 'blind' reference poll.
This because if I have a heart/weight problem and where asked to write down a list of friends "who could be contacted" there are lots of factors that influence my choice of people I write down. I'd guess that one would be more likely to write down a friend with the same problem, and I'd be less likely to write down someone who I know disapprove of the problem (like a fit friend).

[General Zod]

The use of the word "contagious" is misleading. Nowhere in the study do the authors use it. It would be like refering to bell bottoms or mullets as contagious. You don't "catch" a mullet, but if many people around you have them, you begin to see them as a socially acceptable haircut.

That's what I thought when I read the article. I have to wonder what genius at the Beeb thought up the tag-line for it.

[Pulp Hero]

This is true, I know that when I was overweight and would eat with friends, I would often go off my diet because, "well, I'm healthier than that guy."

Now however, it is kind of the opposite because I have a fat room-mate who plays WoW all the time. He motivates me to go out and exercise so that I don't become like him.