Now this is hardcore netocratic thinking.
Fascinating points :
Social network place is inherited (though did he really distinguish genetic vs. educational influences?)
Social networks influence obesity. This serious for me. I've gained going on for 14 kg since returning from Brazil to London. Not, probably, because I'm hanging around with more obese people, but because I and my wife have detached ourselves from a lot of people who take exercise and the appearance of their bodies more seriously.