Friends making you fat?

I cannot believe that the daily rag made this their headline.

The New England Journal of Medicine has made the original article available here. A few things I thought interesting...

• During the study, participants were asked to name a "close friend" who would have their address should the researchers have trouble contacting them. This was the basis for the "close friends" connections in the computer model.
  
  
• The increased correlation of obesity between friends? Is actually between men friends. The paper states that the correlations between female-female and mixed-sex friends were "not significant".
  
  
• According to the NY Times, researchers stated that their calculations showed that on average, "a person who became obese gained 17 pounds and the newly obese person’s friend gained five". When you think "became obese", do you think, "gained 17 pounds"? Or do you think, "gained 70 pounds"? (I'm sure some did gain significantly, at the outside of the bell curve, but it's not the average.)
  
  
• A few years ago obesity researcher Jeffrey M. Friedman reminded us weight is even more hereditary than height. One would expect that siblings would have higher correlations than non-siblings (and identical twins higher than non-twins (study)), which makes all the "friends matter more than siblings" in the media look laughable.
  
  
• On the other hand, in the same article, Friedman says that “people can exert a level of control over their weight within a 10-, perhaps a 15-pound range". Five and 17 pounds is pretty close to that 10 to 15 lb range. Which is interesting.

Computer programs are fun, I spend my work days finding bugs in them :) Toss in that people tend to see what they expect to see, and modeling something like this in software is going to be interesting. But one advantage of this being a model based on free software, and the availability of the Framingham data, is that other researchers can look at this too... ;)

*The Times has it behind the TimeSelect firewall, hence my linking to the copy at CUNY above.