Winter's low humidity and your health: How dry air leads to chapped lips, flaky skin and helps germs grow

The last week of Long Island weather has been cold, snowy and blustery. But one measurement stands out on the misery index: It has been unusually, uncomfortably dry, day after day.

How dry? For January and February over the 30-year-period from 1991 through 2020, Long Island’s mean dew point, a measure of the amount of moisture in the air, was about 21 to 25 degrees, according to the PRISM Group at Oregon State University. By contrast, dew point over the last seven days ranged from minus 7.82 degrees to 10.24 degrees, according to the National Weather Service. (The higher the dew point, the more moisture is present, and vice versa).

It’s been so dry that the National Oceanic and Atmospheric Administration’s Drought Monitor put the region in a moderate drought, receiving 50% to 75% of normal precipitation over the last two months.

Very dry weather like this can have adverse health effects, experts say.

What are the health effects?

One of the most common is itchy skin and chapped lips.

"The biggest thing is dry, cracked hands, or your feet feel dry and cracked," Northwell Health dermatologist Dr. Raman Madan said. "This time of year, it always happens, but it’s almost worse this year than usual."

Young children and older adults are especially susceptible, because their skin barriers, the outermost layers of the epidermis, are relatively weak.

For most people, dry skin is "more of an inconvenience" than a serious health problem, Madan said. But the list of health issues associated with dry air is long: itchy eyes, sore throat, headaches, earaches, dry mouth, constipation and possibly even increased stress, according to a 2025 Cleveland Clinic blog post.

Low humidity can dry out the sinuses, so the mucus there won’t trap pathogens as effectively.

Studies have shown very low humidity is also conducive to increased bacterial and viral growth. A 2019 Yale University School of Medicine study found mice, often used as proxies for humans in biomedical research, were "more susceptible to influenza disease" when exposed to low humidity conditions. Mucociliary clearance — the mechanism by which the lungs protect themselves — was impaired, along with antiviral defense and tissue repair function. In humans, flu can lead to complications, hospitalization and death. 

What are the remedies?

Buy a humidifier, and if it has controls, set it for 40%-50% indoor humidity, Madan said. Humidity that is too high can lead to mold. Setting out a bowl of water to evaporate can also work.

Skin moisturizers work, but look for something with ceramides, lipids that occur naturally in skin, Madan said. "They are a natural ingredient in skin that keeps skin from being dehydrated. Think of skin as bricks and mortar: ceramides are the mortar."

Drinking more water is generally also a good strategy, according to the Cleveland Clinic.

What’s going on with this cold weather, and when will it ease up?

In recent weeks, Long Island’s weather has been coming to us from the west and the north.

"That’s one of the reasons we have been so cold, and it’s also one of the reasons we’ve been drier," said Bryan Ramsey, a meteorologist at the National Weather Service’s Upton station. "Whenever we have a lot of flow coming in from the interior, the continental portions of the United States, away from large bodies of water, we’re getting dry air."

Don’t expect relief anytime soon.

"It’s certainly going to continue into this weekend, because we’re going to take another plunge bringing in more cold air," Ramsey said.

By Nicholas Spangler

nicholas.spangler@newsday.comspanglernewsday

Nicholas Spangler is a general assignment reporter and has worked at Newsday since 2010.