There was a recent article in the New York Times called “Study says obesity can be contagious”. The article is about a recent article in the New England Journal of Medicine that says your chances of gaining/losing weight increases as close friends gain/lose weight. I’m not sure if it is just the reporting or the actual article, but there doesn’t seem to be a hint indicating that it is just correlation. There seems to be a causal mechanism being posited. Here are a couple of choice quotes:
“Obesity can spread from person to person, much like a virus, researchers are reporting today.”
“The investigators say their findings can help explain why Americans have become fatter in recent years — each person who became obese was likely to drag some friends with them.”
“Proximity did not seem to matter: the influence of the friend remained even if the friend was hundreds of miles away.”
I think the best comment upon this is the one that closes the article in which a doctor at Cambridge says that good science is repeatable while this study is unique.

There are probably several things about this to discuss, of which I am competent in more or less none. I don’t know enough about statistics and statistical methodology to comment. There seem to be causal mechanisms posited wildly. I hope this gets discussed somewhere by someone more knowledgable. But, there is a general question that I have based on ignorance. Biology, psychology, and physics get a lot of play in the philosophy of science world. I have a book on the philosophy of linguistics, but I never see anything else about it. Is there much of a sub-discipline of philosophy of medicine (the assumption being that medicine is a science)? There seems to be so much work done in medical research that seems possibly philosophically relevant, but doesn’t get a lot of attention even though (because?) it is in the public eye.