Last year, the Center for Disease Control took time out of its busy day of fighting bird flu to blow our minds with the news that men are gross.

In their study on hand washing, they discovered that only 66 percent of male respondents washed their hands when they used public restrooms, compared to 86 percent of women. But before you celebrate your hygienic superiority, maybe you ought to pour yourself a double shot of Purell.

Just in time for Global Handwashing Day, a U.K. report found that female subjects had more than three times the fecal bacteria on their skin (that's "poo hands") than male subjects.

While the researchers acted totally bewildered, we think we have a pretty simple explanation for these semi-embarrassing results: fingernails. Women tend to wear them a little longer, which makes them more likely to trap, erm, matter underneath. After this, chicks may be willing to risk a case of man-hands for peace of mind while snacking. And for what it's worth, the women we know change a whole lot more diapers than do the dudes ...