Getty Images

Here at, we've occasionally diagnosed ourselves with a hideous ailment after a quick Google search. Isn't it an inalienable Internet right, on par with the ability to view kitten videos or pin pictures of really cool braids on Pinterest? We suspect that the second Google search in history (after 'sex') was probably 'what's this gross rash on my arm?'

The problem is, it's probably--how shall we put this?--not the smartest thing we've ever done. You see, after you plug in your symptoms it's so tempting to diagnose yourself with something like, say bubonic plague, rather than run-of-the-mill eczema. And a new study suggests that yes, that is exactly what Internet "experts" are likely to do.

In the study in the Journal of Consumer Research, Hong Kong researchers gave 250 college students info about a variety of illnesses such as flu, HIV, and breast cancer. The researchers asked the study subjects to make a diagnosis based on whether they themselves had the symptoms or someone else.

Guess what? People are more likely to diagnose themselves with a rare illness than other people with the same symptoms. And that's no minor misstep: It can lead to anxiety, stress, unnecessary (and costly) visits to the doctor, and possibly even stress-induced illnesses.

There is an old medical school saying we've learned (from dreamy actor-doctors on TV, of course), that "when you hear hoofbeats, think horses, not zebras." So if you diagnose yourself with the most horrible illness you can find, guess what? You're making a rookie mistake. That's not to say you shouldn't use the Internet to be more informed before you see the doc--that's just common sense.

Just don't make the leap to zebras (or worse, try to convince your doc you know more than she does--doctors love that).

Better to leave the actual diagnosis up to the professionals.