There are several reasons behind this medical phenomenon.

Cold weather has arrived, and that means we're in for a significant change in temperatures. As the thermometer continues to drop outdoors, it seems as if everyone you know—your colleagues in the office and your loved ones at home—is getting sick. But why, exactly, do so many people fall ill when the weather changes? "Cold weather can stress the immune system," answers Dr. Seuli Bose Brill, Clinical Associate Professor of Internal Medicine at The Ohio State University Wexner Medical Center. "And extreme temperature drops can impair the function of your immune system."

woman with scarf over her face in the cold
Credit: Getty / PeopleImages

And that's not all. While colder temperatures tax your body's built-in defense system, the dryness that typically accompanies chilly weather can also wreak havoc on your internal chemistry. "Reduced humidity in cold weather can cause dryness, such as dry skin and dry nasal passages. This dryness can impair function of our first line of defense against illness," says Brill. "For example, nasal mucous both protects and serves as a barrier against germs."

During the colder months, you're more susceptible to virally driven illnesses, as well. "In addition to impairing the body's first lines of defense against illness, viruses travel more quickly and easily when there is less humidity in the air, which creates a more hospitable environment for viruses that are transmitted from person to person via respiratory droplets—for example, when someone sneezes," says Brill. "There is also some research that shows viruses causing cold symptoms thrive and reproduce more in cold [environments between] 30-40 degrees Fahrenheit."

The chilly temperatures also drive people indoors, and closer quarters always increases your chances of getting sick. "We also spend more time inside in the winter, where viruses have less distance to travel from person to person," says Brill. Luckily, there are simple ways to stay healthy when the weather changes. Following the basics of healthy self-care can help boost your immune system, hold illness at bay, and keep you healthy throughout the season. "Wash your hands frequently. Drink plenty of water to stay hydrated. Get seven to nine hours of sleep per night, as sleep deprivation can weaken your immune system," advises Brill. "Another way to keep your immune system strong is to eat a balanced diet, rich in fruits and vegetables and low in refined sugars."

Comments (1)

Martha Stewart Member
January 13, 2020
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