Fat Is Infectious?

Jonah Lehrer analyzes a new study that finds being exposed to pictures of someone who is overweight makes us prone to consuming more calories:

[T]his research begins to explain how obesity moves through a social network. It turns out that the habits of others shape our own, that we unconsciously regress to the dietary norms around us. Because we’re not particularly good at noticing when we’re sated and full – the stomach is a crude sensory organ – we rely on all sorts of external cues to tell us how much to eat. Many of these cues from other people, which is why our eating habits are so contagious.