The most effective way to prevent a cold is to keep the virus off your hands and out of your nose and eyes. Colds spread primarily through airborne droplets and through touching contaminated surfaces then touching your face. Since there’s no vaccine for the common cold, prevention comes down to a handful of daily habits that reduce your exposure and keep your immune system functioning well.
How Colds Actually Spread
Rhinoviruses, the most common cause of colds, travel in two main ways. The primary route is airborne: when someone nearby coughs, sneezes, or even talks, tiny droplets carrying the virus enter your nose or mouth. The second route is hand-to-face contact. You touch a doorknob, phone, or countertop where someone left virus particles, then rub your eye or touch your nose. This hand-nose-hand cycle is one of the most frequent ways people infect themselves.
Rhinoviruses can survive on hard surfaces like stainless steel, countertops, and wood for up to three hours. Fabric surfaces like wool and nylon also harbor the virus for similar periods. That means a break room table wiped down in the morning could still carry live virus at lunch.
Wash Your Hands for 20 Seconds
Handwashing is the single most practical thing you can do. The CDC recommends scrubbing with soap and water for at least 20 seconds to remove harmful germs. That’s roughly the time it takes to hum “Happy Birthday” twice. Focus on the moments that matter most: after being in a public space, before eating, after blowing your nose, and after shaking hands.
When soap and water aren’t available, an alcohol-based hand sanitizer with at least 60% alcohol is a good backup. Keep a small bottle in your bag, car, or desk drawer so it’s always within reach during cold season.
Keep Your Hands Away From Your Face
This sounds simple, but most people touch their face dozens of times per hour without realizing it. Every time your finger touches your nose or the corner of your eye, you’re giving any virus on your skin a direct path to your mucous membranes, exactly where it needs to go to start an infection. Building awareness of this habit is half the battle. Some people find it helps to keep their hands busy, use a tissue when they need to scratch their nose, or simply notice how often they do it over the course of a day.
Sleep More Than Six Hours
Sleep is one of the strongest predictors of whether you’ll catch a cold after being exposed to a virus. A study published in the journal SLEEP deliberately exposed participants to rhinovirus and tracked who got sick. People sleeping fewer than five hours per night were 4.5 times more likely to develop a cold compared to those sleeping more than seven hours. Sleeping five to six hours carried a nearly identical risk, at 4.24 times more likely. The jump in protection happened right around the six-hour mark: people getting between six and seven hours showed no statistically significant increase in risk compared to the seven-plus-hour group.
That means getting consistently above six hours, and ideally above seven, is one of the most impactful things you can do during cold season. If you’re running on five hours of sleep and riding the subway every morning, your odds of catching the virus circulating around you are dramatically higher.
Stay Active, but Keep It Moderate
Regular moderate exercise supports immune function and is associated with fewer upper respiratory infections. The key word is moderate. A daily 20- to 30-minute walk, biking with your kids a few times a week, or hitting the gym every other day all qualify. The benefit comes from consistency over intensity. People who follow a moderately active lifestyle and stick with it tend to get the most immune benefit.
Extreme or prolonged intense exercise, on the other hand, can temporarily suppress immune function, which is why marathon runners often get sick in the days after a race. For everyday cold prevention, a regular walking habit is more useful than occasional hard workouts.
Manage Indoor Humidity
Dry indoor air, common in winter when heating systems run constantly, helps respiratory viruses survive longer and travel farther. Research from MIT found that maintaining indoor relative humidity between 40 and 60 percent is associated with lower rates of respiratory illness. Conditions outside that range, either too dry or too humid, were linked to worse outcomes.
A simple hygrometer (available for a few dollars at most hardware stores) lets you monitor your home or office. If humidity drops below 40 percent, a room humidifier can bring it back into range. This is especially worth paying attention to in heated offices and bedrooms during winter months, exactly when cold season peaks.
Try Saline Nasal Drops
Rinsing the nasal passages with salt water may help reduce your viral load and limit spread within your household. In a trial of over 400 children, those given hypertonic saline nasal drops when they developed a cold recovered faster, and family members in those households were less likely to catch the cold (46% of households reported spread, compared to 61% in the usual-care group). The chloride in salt helps cells lining the upper airway produce more of a natural antiviral substance that suppresses viral replication.
Saline sprays and drops are inexpensive, widely available, and safe for daily use. While most of the evidence relates to reducing duration and household spread rather than preventing initial infection, keeping nasal passages moist and flushed is a low-risk strategy during cold season.
What About Vitamin C, Zinc, and Vitamin D?
These three supplements are the ones people reach for most often, but the evidence for prevention specifically is mixed. High-dose vitamin C can reduce the severity and duration of cold symptoms once you’re already sick, but it hasn’t been shown to reliably prevent colds in the general population. Zinc supplements at higher doses shorten how long a cold lasts, though the evidence for taking zinc as a daily preventive measure is inconclusive. Vitamin D supplementation has been linked to a lower incidence of acute respiratory infections, but the effect is strongest in people who are already deficient. If your vitamin D levels are normal, extra supplementation may not add much protection.
In practical terms, standard over-the-counter doses of these supplements carry little risk. But they’re best thought of as supporting players rather than primary defenses. Correcting a genuine deficiency in vitamin D, for instance, is worth doing. Megadosing vitamin C when you already eat a balanced diet is less likely to make a meaningful difference.
Clean Shared Surfaces
Because rhinoviruses can survive on hard surfaces for up to three hours, regularly wiping down frequently touched objects makes a real difference, especially during peak cold season or when someone in your household is sick. Focus on the surfaces hands touch most: light switches, door handles, phone screens, keyboards, faucet handles, and remote controls. Any EPA-registered disinfectant labeled as effective against viruses will work. Check the product label to confirm it lists viruses among the pathogens it targets.
Extra Steps During Peak Season
The CDC recommends layering additional precautions when respiratory viruses are circulating heavily in your community. Wearing a mask in crowded indoor spaces reduces your exposure to airborne droplets. Keeping distance from people who are visibly sick helps too. If you’re the one who’s sick, staying home until you’re no longer symptomatic is the most important thing you can do for the people around you.
Improving ventilation matters as well. Opening a window, running an air purifier, or simply spending more time outdoors all reduce the concentration of viral particles in the air you breathe. Combined with handwashing, adequate sleep, and regular exercise, these steps add up to a meaningful reduction in your chances of catching a cold this season.