The most basic, life-saving hygiene -- washing your hands -- takes about 20 seconds. The Centers for Disease Control says this simple task can prevent the spread of deadly foodborne illnesses and infections and curb your chances of catching a cold or the flu. And, yet, 95 percent of us aren't doing it right, according to a study by researchers at Michigan State University.

Researchers camped out in public restrooms to observe hand-washing practices (which is creepy, but all in the name of science, folks) and found that only five percent of people followed proper hand-washing guidelines. Of the more than 3,700 people observed in the study, 33 percent didn't use soap, 10 percent skipped out without washing at all, and the average hand-washing time was a grand total of six seconds.

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And from the Department of We Could've Guessed That: The study, published in the June issue of the "Journal of Environmental Health," found that men are far lazier than women when it comes to hand-washing habits. Fifteen percent of men didn't wash compared to 7 percent of women who skipped out on soap and water. When they did bother to wash, only 50 percent of the men used soap, compared to 79 percent of women.

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The best part? The researchers acknowledged that their presence alone -- even as clandestine observers -- could've skewed the study, pressuring more people to wash than if they were alone in the restroom. Think about the last 10 people you shook hands with, and let that one sink in.

No soap and water? No worries. The CDC recommends using an alcohol-based hand sanitizer with at least 60 percent alcohol. Click to see member ratings on hand sanitizers and wipes.