We do a pretty shoddy job at washing our hands after using the restroom.

That's the finding of a recent study in the Journal of Environmental Health, showing that only 5 percent of people wash their hands for 15 to 20 seconds, which is the amount of time the Centers for Disease Control and Prevention says you need to kill bacteria, in order to prevent the spread of diseases.

Instead, we spend about 6 seconds washing our hands on average.

"These findings were surprising to us because past research suggested that proper hand washing is occurring at a much higher rate," study researcher Carl Borchgrevink, an associate professor of hospitality business at Michigan State University, said in a statement.

The study included 3,749 people who used public restrooms in bars, restaurants and other locations, who were watched by a team of college students observing casually from the side.

Researchers found that 33 percent of people didn't use soap after washing their hands, and 10 percent didn't even lather up after using the restroom. They also found that men were less likely to wash their hands than women -- 15 percent of men versus 7 percent of women -- and were also less likely to use soap than women -- 50 percent of men versus 78 percent of women.

Environmental factors seemed to play a role, too. Particularly, if the sink was dirty, people were less likely to wash their hands. And if there was a sign reminding people to wash their hands, they were more likely to do it.

This particular finding seems to fall in line with a recent study in the journal Human Communication Research, showing that men are more likely to wash their hands after using the restroom if they're exposed to relatable reminder signs in the bathroom.

So what's the best way to wash your hands, anyway? According to the CDC, you should first wet your hands with clean water, then get some soap and work it into a lather. Scrub your hands together for at least 20 seconds, and then rinse before drying.

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  • Hand Washing
    There may be no more promoted solution to avoiding the flu this year (besides the flu shot, of course) than diligent hand washing. As many as 80 percent of infections are transmitted via contact like sneezing, coughing or touching surfaces that have been sneezed or coughed on, says Tierno, and then touching "your mouth, eyes or nose, which are the conduits of viruses into the body." He recommends scrubbing before eating, drinking or touching your face, and disinfecting shared surfaces in the home (like the bathroom) and the office, like phones, computers and fridge door handles.
  • Sleep
    While you're off in dreamland, your body gets to work repairing cells and injuries you may have incurred during the normal day's wear and tear, says Tierno. Getting your seven to nine hours a night means your body can repair and heal itself and ward off infections. "If you don't get the appropriate sleep, that system is not operating and you're on a steady decline over time," he says. In fact, skimping on sleep is as disruptive to the immune system as stress, according to a 2012 study. And earlier research suggested that sleep patterns may play a role in a gene that helps fight off bacteria and viruses.
  • Exercise
    Getting your blood pumping regularly can increase the activity of a type of white blood cells that attacks viruses. Shoot for an hour a day, says Tierno -- but not necessarily all at once. "Even if it's walking around the office, up stairs, down stairs, to and from work -- it doesn't have to be continuous," he says.
  • Zinc
    Getting the proper amount of the right nutrients and minerals as part of a healthy diet "leaves the body in optimal condition to fight the battle," says Tierno. This means cutting back on sugary, fatty foods and upping your intake of vegetables, fruit and lean protein, he says. One of those nutrients that gets a particularly healthy reputation during cold and flu season is zinc, and for good reason. "Zinc interferes with viruses gaining full access to our cells," he says. "Zinc may block certain metabolic activity." While it's not the end-all cure, foods rich in zinc, like oysters and wheat germ, may offer some protection.
  • Garlic
    The anti-microbial properties of this pungent bulb (and its relative, the onion) can fight off certain bacteria and viruses, says Tierno, as can the compounds in other herbs and spices, like thyme. It's likely due to the compound allicin, which seems to block infections. Try it in your next bowl of soothing chicken soup!
  • Water
    Thankfully, most of us are inhabiting cozy-warm homes this winter, but those cranking radiators come with a downside. Indoor winter air is much dryer than our bodies would like. Without sufficient moisture, says Tierno, "immune system cells can't optimally work," so it's important to stay hydrated. (A humidifier can also help.)
  • Skipping Happy Hour
    Alcohol suppresses both the part of the immune system that protects you from coming down with something and the part that fights off the germs already in your system, so knocking a few too many back can put you at increased risk for catching the bug going around -- and having trouble kicking it.
  • Laughter
    A positive attitude can take you far -- even, maybe, to age 100. But along the way, a life of laughter and optimism could also help you sniffle through fewer bouts of the flu or colds. While there's much that's still not well understood about the process, it seems that certain immune cells are produced by a big belly laugh, says Tierno.
  • Massage
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    A favorite solution for de-stressing, massage can also help you stay physically healthy. While there's been little research into exactly how it works, massage certainly increases circulation, which may help promote the general "state of wellness in the body," says Tierno. "Nutrients are passed around better, the blood flow is better," he says. "It's a very useful thing to get a massage."
  • Sex
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    A 1999 study found that getting frisky a couple of times a week can boost immunoglobin A, an antibody that fights off colds. Just make sure your partner isn't already sick!