Health roundup: Vitamin D fails to prevent colds

Your Wednesday morning health roundup:

Vitamin D study: Taking vitamin D supplements to prevent colds? You may be wasting your money. A rigorous new study finds that people taking large doses of the popular supplement were just as likely to get colds as people not taking them and that their symptoms lasted just as long. Researchers haven't given up on the idea that supplements might help some people who have very low blood levels of the vitamin. (WebMD)

Teen drivers: Drunk driving among teens fell by more than half in the past 20 years, thanks in part to laws curbing underage drinking -- but also thanks to the fact that teens drive less overall. Rising gas prices also played a role, says the Centers for Disease Control and Prevention. About 10% of high school students admitted drinking and driving in 2011. (Bloomberg)

Meningitis outbreak: An unusual outbreak of fungal meningitis -- infection of the membranes covering the brain and spinal cord -- has killed two people in Tennessee and sickened 12 others, including one person in North Carolina, health officials say. The infections have been linked to steroid injections the patients got in their spines and a possibly-contaminated drug has been recalled. (New York Times)

Today's talker: Video of a teenager who licks an entire New York City subway railing on a dare -- for a paltry $1 -- is making the Internet rounds. It's gross, but the folks at NBC News' Body Odd blog stop to ask just how gross it is. Answer: probably worse than licking a toilet seat. That handrail may host hundreds of thousands of germs. And yet, the chances the kid will get sick are pretty low -- unless he is unlucky enough to slurp up some fecal matter. Good to know.