A great article from the BBC, “The Surprising Downsides of Being Clever”:

Constant worrying may, in fact, be a sign of intelligence – but not in the way these armchair philosophers had imagined. Interviewing students on campus about various topics of discussion, Alexander Penney at MacEwan University in Canada found that those with the higher IQ did indeed feel more anxiety throughout the day. Interestingly, most worries were mundane, day-to-day concerns, though; the high-IQ students were far more likely to be replaying an awkward conversation, than asking the “big questions”. “It’s not that their worries were more profound, but they are just worrying more often about more things,” says Penney. “If something negative happened, they thought about it more.”

I’m not sure any of the downsides discussed are all that surprising, though.  The biggest trap of being smart is probably realizing your own intelligence, which in effect causes you to unjustifiably underestimate others.  In my experience it’s best to assume you’re not the smartest person in the room even if you actually are.

But what do I know?  Presumably I’m not that smart.