Exercise and healthful eating are linked to better health—and so is having a decent circle of friends. Now it looks like that link between friends and better health is true for the major online social network, too: Facebook.
Researchers compared the health records of 12 million Facebook users to non-users, in California. After controlling for things like age, race, and gender, they found that being on Facebook was associated with a slightly lower risk of death in a given year.
Now, some of that could be explained by the fact that Facebook users might be more affluent, or have better access to healthcare. So the researchers did a second analysis—by looking only at Facebook and non-Facebook users on the California voter rolls, a sort of proxy control for socioeconomic status. And the association still held up. The study is in the Proceedings of the National Academy of Sciences.（PNAS） [William R. Hobbs et al., Online social integration is associated with reduced mortality risk]
Of course correlation does not equal to causation (相关性并不意味着有因果关系). Posting more photos isn't going to increase your lifespan. But the takeaway here is that, in some cases—like when people tag you in their photos—that online world can reflect real world ties. Interactions on Facebook are thus reflective of（Be reflective of: 反映了） your actual human relationships—and might even reinforce them. Which certainly seems like a thumbs up.