“Bundle Up! You’ll Catch a Cold!”

Who hasn’t been scolded by a parent or grandparent for leaving a jacket unzipped, not wearing a hat, leaving the house with wet hair or failing to tuck in a scarf — with the admonition that you’re inviting illness by doing so? Or perhaps you’ve been the one to deliver that warning.

“My grandmother used to tell me the same things that most people’s grandmothers tell them: ‘Make sure your head is covered!'” says Randy Bergen, MD, a pediatrician and clinical lead of the flu vaccine program for Kaiser Permanente in northern California. “But there’s no evidence that going outside without a hat can cause the constellation of symptoms associated with the common cold.”

Symptoms & Causes
Those symptoms include congestion, cough and sometimes fever and achiness, says Dr. Bergen. “It’s caused by a virus that infects the respiratory tract — the nose, the throat, sinuses and sometimes the chest.”

There are a number of viruses that can do this, he says, including the rhinovirus and coronavirus, two of the most common. “The list of viruses that can cause a cold seems to grow every year,” he adds. “It’s an infection that tends to be more common during the winter, when people are close together indoors. It’s a relatively contagious infection, and, therefore, few people manage to go through an entire winter without a catching a cold.”

Another common mistake, says Dr. Bergen, is confusing a cold with the flu. “There is a specific wintertime virus called influenza,” he says. “Of all the viruses, it is in general the most severe. It sweeps through communities each and every winter season. It is a distinct virus, for which we have a vaccine, and we encourage people to get vaccinated every year.”

Flu symptoms can include those associated with the common cold but are typically more severe. They may also include a fever and feverish chills, a sore throat, headaches, vomiting and diarrhea. The flu can last from a few days to as long as two weeks.

Who’s at Risk
While anyone can get the flu, some people — such as those over the age of 65, young children and those with weakened immune systems due to chronic illness — are at higher risk. The Centers for Disease Control and Prevention (CDC) recommends that people over the age of six months receive a flu vaccine each year unless they are allergic to the vaccine or any of its ingredients, such as eggs.

Because the flu can lead to pneumonia in people whose immune systems are weakened, the CDC also recommends the pneumonia vaccine (in two doses) for adults over the age of 65 and others at high risk. Most pharmacies offer flu and pneumonia vaccinations, and often you don’t need an appointment.

There are no vaccines to prevent the viruses that cause colds, says Dr. Bergen. But vaccines aren’t the only way to prevent illness.

Staying Healthy
Maintaining lifelong healthy habits can help protect you from the more than 200 cold and flu viruses that circulate each year. These include frequent hand washing, eating a healthful diet rich in antioxidants from fruits and vegetables, getting enough rest, managing stress and exercising regularly.

Not smoking (or quitting if you do smoke) also helps to protect against illness. Keeping your home clean is also important, especially if someone in the home is sick, because germs can be spread by touching counter tops, toys, telephones and bathroom sinks, for example.

“The single best way that we can try to stay healthy is to prevent those germs from getting to us,” says Dr. Bergen. “To the best of your ability, stay away from sick people. Try to avoid dense concentrations of people where there is more likely to be illness, since these viruses are airborne.”

“If you are sick,” he says, “cover your cough. Don’t go to work.”

Getting plenty of vitamins C and D can also help to prevent illness by boosting the body’s immune system, says Dr. Bergen. While taking supplements can help, he advises people to try to get these vitamins into their diet naturally. “I would much prefer that my patients eat citrus fruits than take supplements of vitamin C. I prefer people to make healthy food choices — that’s the best way to keep your immune system strong.”

There is little evidence that products such as zinc or echinacea prevent the common cold, but no evidence that they cause harm, either, says Dr. Bergen. “There is some evidence that they may make it more difficult for the virus to attach to respiratory mucus, so taking these products at the start of symptoms may help you a bit and certainly won’t hurt.”