Employers are pushing flu shots. Kids are bringing germs back from school. Your sniffly co-workers are too scared of looking lazy to stay home when they ought to.
How can you protect yourself from the microbial swamp of the cooler months?
Everybody's got a theory—orange juice, neti pots, raw ginger. Science hasn’t found a cure for the common cold, but it’s investigated a lot of possible candidates. Here’s your science-based guide to what works, and what doesn't, when you’re trying to stay healthy during cold and flu season.
Flu shots help
Flu viruses kill thousands of people each year in the U.S., mostly the elderly or people with other health problems. Since 2010, the Centers for Disease Control has recommended flu shots for everyone except infants younger than six months or people who are severely allergic to the vaccine. In healthy adults, flu vaccines can reduce illness and sick days. The effect is “very modest,” according to reviewers from the Cochrane Library, which pools medical studies and evaluates the evidence. At least 40 people need to be vaccinated to prevent one illness, the research suggests. But getting healthy people vaccinated is important to protect the more vulnerable. “The more of us that get the vaccines, the less likely all of us are to get sick,” said Donald Ford, a family physician at the Cleveland Clinic.
Vitamin C and zinc don’t do much
Vitamin C doesn’t prevent colds1, according to evidence from dozens of trials involving more than 11,000 people. There’s some evidence that people who were already taking C supplements had slightly shorter colds when they got sick. But waiting until your cold starts to take vitamin C doesn’t seem to do anything, though researchers note that more studies are needed. Limited evidence suggests zinc may slightly reduce the length of colds, and zinc supplements are widely marketed as remedies. But doctors don't recommend zinc for colds. It can have side effects, sometimes serious ones: The Food and Drug Administration warned about zinc nasal sprays in 2009 after 130 people reported they lost the sense of smell.
Antibiotics aren’t for viruses
Antibiotics can kill bacteria, not viruses. They’re useless against the common cold or flu. Doctors sometimes prescribe them anyway, particularly if patients badger them. Don’t. Unless you have another, bacterial infection, antibiotics won't help. They will increase the risk of side effects such as diarrhea, though. And misuse of antibiotics contributes to the rise of drug-resistant superbugs in the population as a whole.
Garlic needs more research
While the value of garlic in the kitchen isn't disputed, the evidence for keeping it in your medicine cabinet is thin. Reviewers found one trial with 146 people that reported that three months of garlic supplements seemed to reduce the frequency of colds compared with a placebo. More studies are needed to validate that finding. Most of garlic's health claims "rely largely on poor-quality evidence,” Cochrane reviewers wrote. Possible side effects: rash, and smelling like garlic.
Echinacea: minor benefits possible
The case for using echinacea to treat a cold is shaky. “It is possible there is a weak benefit,” according to the Cochrane review. Trials for prevention indicated "small preventive effects," though patients experienced more side effects than patients taking a placebo, including allergic reactions.
In short, there’s not much evidence to support a lot of the stuff people think helps. So beyond getting a flu shot, what should you do?
Take care of yourself
Eating well, exercising, and managing other medical conditions can help you stay healthy, said Pritish Tosh, an infectious-disease doctor at the Mayo Clinic in Rochester, Minn. Sleep and peace of mind help, too. “In general, we find that when people have a lot of stress or have sleep deprivation, there’s a lot of health problems that result,” Tosh said. "That can include becoming more susceptible to infections."
Wash your hands and cough and sneeze into your arm
"The single most effective prevention for the spread of viruses is hand hygiene," said the Cleveland Clinic’s Ford. Viruses expelled when people sneeze, cough, or talk can linger on desks, doorknobs, elevator buttons, and other surfaces. Practice the vampire sneeze into the crook of your arm.
Rest and fluids
If you do get sick, get lots of rest and drink plenty of fluids. It’s the best way you can help your body clear an infection that will go away on its own.
When people try to power through an illness, “they actually make it worse for the people around them, and they make it worse for themselves,” Tosh said. (Doctors and nurses are bad at following this advice.) People are often most contagious during the early stages of a viral infection. Staying home when you first get sick can protect your co-workers and give your body more rest. It's a tricky calculation for some. “Many people in this country don’t get paid if they don’t go to work,” Ford noted. If you can afford to, do everyone a favor and take a sick day.