Germs are everywhere, and for those who are particularly concerned about catching a cold or infection, hand sanitizers can seem like the answer. Just a little squirt, many people think, can protect you from the nasty bugs that are everywhere in our daily life. But recently, doctors and scientists have come to realize that hand sanitizers aren’t necessarily the boon we all thought. Here’s why you need to worry about hand sanitizers: Using them too much may have dire consequences to our hand microbiome, the “good” bacteria that keep our skin, and our bodies, healthy. “There’s no question that use of hand sanitizer—not just overuse, probably any use—will ‘disrupt’ the hand microbiome,” says David Coil, PhD, a microbiologist at the UC Davis Genome Center. “The stuff really does kill a lot of microbes.” Hand sanitizer could wipe out the good bugs along with the bad; but as research is still ongoing about what constitutes a healthy hand microbiome, it can be hard to determine how much sanitizing is too much.
In this article, we’re referring to hand sanitizers that use at least 60 percent alcohol to kill germs. The Food and Drug Administration has recently updated what ingredients are allowed in hand sanitizers, so really harmful substances, such as triclosan, should no longer be in them. Still, the average consumer may want to think twice about hand sanitizers. Here are some situations where you might be overusing the products.
You have access to soap and water
You don’t need to use hand sanitizer to stay germ-free. In fact, hand sanitizers should always take a back seat to plain old soap and water: According to the U.S. Centers for Disease Control and Prevention (CDC), the best way to get rid of germs is by proper hand-washing, which physically removes the bugs and washes them down the drain. “Soap and water is always a great way to clean your hands,” says Graham Snyder, MD, medical director of infection prevention at UPMC. “At home, soap and water should be the go-to method. Alcohol-based hand sanitizer can be helpful when soap and water are not available.” Using hand sanitizer can seem easier than taking a trip to the sink, but if one is available, you should use it. “Soap and water is preferable in all situations which it’s possible,” Dr. Coil says.
Your hands are visibly dirty
Anyone who’s tried to use hand sanitizer to clean dirt off their hands knows this just creates a muddy mess. “Alcohol-based hand sanitizers do not remove dirt, and are less effective at killing bacteria and viruses when hands are soiled,” Dr. Snyder says. “It’s important to use soap and water if your hands need to be cleaned of dirt.” So after participating in sports, gardening, or playing outside, avoid the hand sanitizer.
You’ve been handling chemicals
The CDC also notes that hand sanitizers are probably not very effective at getting rid of contaminants from harmful chemicals such as pesticides or heavy metals. In one study on farm workers, those who used hand sanitizer to clean their hands had increased levels of pesticides in their bodies than those who didn’t. Although more research is needed, if you’re handling hazardous materials, don’t rely on hand sanitizer. Wash your hands thoroughly afterward.
When someone sneezes next to you
If you’re at the office or on the train and a sick person is coughing and sneezing close to you, your first instinct might be to reach for the hand sanitizer. But, chances are you’ll catch their infection through the air droplets you’re breathing in, not the germs on your hands. “Contaminated hands are only one way to get sick with an infection,” Dr. Snyder says. “Other ways to pick up a germ that can cause infection include inhaling germs in the air; for example, influenza.” To better prevent the flu, be sure to a yearly a flu shot; and remember other ways to avoid getting sick such as preventing insect bites, and properly preparing and storing food.
You haven’t touched anyone or anything else
You might be putting on hand sanitizer without even thinking about what you did or didn’t touch; it’s just habit. But, this overuse could actually create resistant bacteria, according to a recent study. “They pretty convincingly showed that those bacteria have become more resistant over time, and even test the relevance of that finding in mice,” Dr. Coil says. “It’s really not surprising: Bacteria can, and have, evolve to develop resistance to pretty much anything.” So the more we use hand sanitizer routinely, the greater the likelihood germs may become tolerant of the alcohol. Reserve using the stuff for when it’s really necessary.
You’re in the middle of an outing
In trying to cut back on using hand sanitizers, some experts say it’s probably not necessary even when you’re out and about unless you’re going to eat and can’t wash your hands. “I personally think it’s totally unnecessary in places like grocery stores,” Dr. Coil says. Instead, avoid touching your face to prevent any hand germs from getting into your body until you have access to a sink. When you get home, wash your hands right away.
You just sanitized five minutes ago
The more you use hand sanitizer, the more your skin won’t like it, which is why it’s one of the 10 things dermatologists refuse to use on their hands. “I think that irritation or drying out are both certainly possible from overuse,” Dr. Coil says. And ironically, might there a risk of skin that’s dry and cracked leading to more infection? “It at least seems plausible,” he says. If you’re going to use hand sanitizer, instead of constantly reapplying, do it once properly right after contamination occurs, such as after shaking someone’s hand (this is because hand sanitizer last hours less than you thought it did): The CDC says to rub over all surfaces of both hands until your hands are dry, about 20 seconds. Plus, make sure you don’t wipe it off.
You’ve touched raw meat
It should go without saying that before and after you prepare food, wash your hands because hand sanitizers aren’t going to cut it. Raw meat and fish can make hands greasy, which the CDC notes will cause hand sanitizers not to work as well. The FDA’s guide for food service workers also stresses that hand sanitizer cannot be used in place of hand-washing. So after preparing food or after going fishing, use soap and water instead.
You’re on a cruise
Cruisers beware: The hand sanitizers you stocked up on before you set sail might not do much against norovirus, the gastrointestinal illness that has been known to make its way around cruise ships. “A few bad germs may not be removed or killed as well with alcohol-based hand sanitizers as with soap and water—norovirus, a virus that causes vomiting and diarrhea, is one of these germs,” Dr. Snyder says.
When someone’s throwing up
But norovirus doesn’t just attack on ships, so be vigilant about hand-washing whenever GI symptoms are present in a family member or coworker: It’s one of the 8 crucial tips for avoiding the dreaded stomach flu. “If you or someone at home is sick with vomiting or diarrhea, washing your hands with soap and water is a better way than alcohol-based hand sanitizers to prevent others from getting sick,” Dr. Snyder says. And remember that trying to avoid all germs with hand sanitizer can create a false sense of security, Dr. Coil says. “Say you are working somewhere where there are a lot of people touching a lot of things, so you use hand sanitizer to ‘protect yourself from germs,’” he says. “And then you get norovirus, which you would have avoided if you had just been washing your hands well with soap and water.”
You’re around children
Although hand sanitizer is safe to use on kids, the CDC notes some concerns regarding children having regular access to it. “Using alcohol-based hand sanitizers as they are intended for use on the hands will not result in any significant absorption of alcohol into the body,” Dr. Snyder says. But, “ingestion or inhalation of alcohol-based hand rub may result in injury or toxicity.” Hand sanitizer is often not in a child-proof container, and from 2011 to 2015 U.S. poison control centers received almost 85,000 calls about hand sanitizer exposures in children. Hand sanitizer-lovers should be aware of the risks involved in keeping it easily accessible in purses, cars, and around the house.
You should be homesick
If you think that using hand sanitizer after you blow your nose means you’re good to go out when you’re sick, think again. “Hand hygiene is an essential way to prevent many infections, but preventing infections also includes…staying home when we’re sick to prevent infecting others,” Dr. Snyder says.
You’ve just gone to the bathroom
If you’re using a porta-potty, hand sanitizer might be your only option for cleaning your hands. But if you can get to a sink, once again: Use it. The same goes for after you’ve changed a dirty diaper, touched animals, or handled garbage. According to the CDC, any situation you’d regard as generally germy is going to be better neutralized with soap and water. The only time to use hand sanitizer in these cases is if you truly have no access to a sink. To recap why: “Hand sanitizers are probably not great for your skin, they lead to resistance, they create a false sense of security, and they displace soap and water which is preferable anyway,” Dr. Coil says. If you’re looking for ways to get rid of all the extra hand sanitizer you now have, try these 21 genius uses of hand sanitizer you’ll wish you knew before.