Men are dirtier than women. So scientists confirmed by spying in public restrooms, watching as one-quarter of men left without washing their hands. In contrast, 90 percent of the women did wash up.

What’s this got to do with the Atlanta Metroblog you ask?

The worst offenders were at an Atlanta Braves game.

Back in 1996, the society first studied how often people follow mom’s advice to always wash up after using the toilet. Researchers lingered in public restrooms, putting on makeup or combing their hair, while surreptitiously counting. They concluded about one-third of people did not wash.

The group sponsored an education campaign about how hand-washing can stop the spread of flu, diarrhea and other infectious diseases. Every few years, researchers repeat the spying.

This time, 83 percent of people washed, reported Harris Interactive, a research company that last month monitored more than 6,300 public restroom users for the society.

That is a little better overall. But take a closer look:

ï The worst hygiene was at Atlanta’s Turner Field baseball stadium, where 37 percent of men left the bathroom without washing, and 16 percent of the women did.

ï New York’s Penn Station had the biggest gender disparity, where 64 percent of men washed their hands compared with 92 percent of women. Grand Central Station was almost as bad.

ï The best hygiene was at San Francisco’s Ferry Terminal Farmers Market and Chicago’s Museum of Science and Industry and Shedd Aquarium, where only about 12 percent of people left without washing.

People exaggerate about hygiene. A Harris telephone survey of 1,000 more adults found 91 percent insisted they wash in public restrooms. Additionally, 77 percent claimed to always wash before handling or eating food, and 32 percent after coughing or sneezing.

It is hard to double-check the latter claims. But the Centers for Disease Control and Prevention says poor hand-washing contributes to almost half of all foodborne disease outbreaks.

With influenza season approaching, microbiologists warn that it is easy to catch a cold or the flu by shaking hands with someone who just used that hand to cover a sneeze. The viruses can stay alive for two hours on hands, and for 20 minutes on hard, dry surfaces those germy hands touch.

So sneeze into your elbow instead and wash frequently. There is no need for special anti-bacterial cleansers, Daly said, although alcohol-based hand gels can substitute when soap’s not available.

Seriously, wash your hands guys… It’s just common sense.