Busting Medical Myths Even Docto...(/p Then there's the one about hair and...),Health

Then, there's the one about hair and fingernails continuing to grow after death -- the so-called Dracula effect. What actually happens, Vreeman and Carroll write, is that the skin retracts after death, giving the illusion of growth. That's part of something that happens during life, too -- we grow "long in the tooth," not because old teeth are growing, but because the gums that support them shrink.

There's an air of scientific verisimilitude about another myth cited by Vreeman and Carroll -- that eating turkey makes you sleepy. Supposedly, that happens because turkey is rich in the sleep-inducing amino acid tryptophan, but the tryptophan content is not great enough to bother anyone, Vreeland said. It's probably the wine that comes with the Thanksgiving turkey that lowers the eyelids.

As for drinking eight glasses of water a day, don't try it. Water comes into the body via a number of foods, such as fruits and vegetables, and a zealous endeavor to meet the eight-glass quota might even be dangerous, Vreeman said.

She and Carroll are expanding their myth-busting effort. "We're in the process of writing a book with over 100 of them," Vreeman said.

Have you heard the one about chewing gum staying in your stomach for seven years if you swallow it?

More information

For a clear-eyed take on other medical myths, visit the University of Arkansas for Medical Sciences.

SOURCES: Rachel Vreeman, fellow, children's health services research, Indiana University School of Medicine, Indianapolis; Graham F. Greene, M.D., associate professor of urology, University of Arkansas for Medical Sciences College of Medicine, Little Rock; Dec. 22-29, 2007, British Medical Journal