Your health

Pass the smell test

How you smell depends on your genes. Or, more precisely, your mate's genes.

Researchers at Duke University Medical Center wondered why the same sweaty man smells sexy to one person and disgusting to another. So they asked 391 volunteers to smell samples of two sex-steroid chemicals commonly excreted in sweat and urine.

Descriptions of the odors ranged from no smell at all, to "vanilla and sweet" and "sickening and urine." When the scientists performed genetic analysis on blood samples from the sniffers, they were able to link specific genetic variants to specific perceptions of smell.

Many theories exist on why we prefer certain smells; everything from culture to memory could play a role. This new study adds genes to the mix.

Get healthy lungs

The American College of Chest Physicians has some new advice on whether you should get a CT scan to screen for lung cancer:

Don't bother.

There isn't enough evidence to show CT screening will prevent deaths, ACCP says in new guidelines issued this month. That goes for everyone, even smokers and others at high risk.

You also don't need to bulk up on vitamins. Beta-carotene and vitamin A could actually increase your risk, and vitamin E won't make any difference.

The best thing you can do, chest physicians say, is not to smoke.

Dirty little secret

Chicago, give yourself a (clean) hand. The American Society for Microbiology sent spies out to public restrooms in four U.S. cities this year, and Chicago scored highest in the percentage of people who wash their hands.

Observers hung out in the bathrooms at the Museum of Science and Industry and the Shedd Aquarium and secretly counted how many men and women washed up after using the toilet. On average, 81 percent of people washed. That's down from 88 percent in the same locations two years ago, but still good enough to beat New York, Atlanta and San Francisco.

-- Susan Stevens