Learn how the hot, dry, indoor air common in cold climates during the winter can affect your child’s health, whether humidifying the air is a good idea, and how you can humidify safely.
Winter fun is filled with cold outdoor activities that kindle warm memories, from building snowmen to sledding, snowball fights to skiing. But when the winds of winter pick up—and give your little snow angels colds and coughs—you don’t want those frigid gusts blowing inside your house. You close the door tight behind you to keep the cold air out. You switch your screens for storm windows. The heat blasts through the vents, and the fireplace is the favorite family gathering spot.
By January, the furnace-induced warm air of winter has settled into your home—or, more accurately, it has been locked in like a prisoner. The fresh air that was able to breeze through open windows and screen doors in spring, summer, and fall is left outside. The imprisoned air is sucked of its moisture by the furnace and fires. It is dry, dry, dry.
That’s not a good thing for those colds and coughs. In fact, it may be part of the cause of those illnesses. Dr. Jay Gordon, MD, FAAP, a pediatrician in private practice in Santa Monica, California, says, “The reason kids get sick in the winter isn’t the cold weather. It’s the warm, dry air indoors.”
How Indoor Air is Harmful
Indoor air pulls a one-two punch. Hot, dry air dries out the mucus membranes of the throat and nose and makes them less effective barriers against infection. Hence, more colds and coughs. Then, after your child gets sick and congested, he stops breathing through his nose and breathes through his mouth.
“The nose is a great humidifier, even in the desert,” says Dr. Gerald Loughlin, MD, chairman of the pediatrics department at Weill-Cornell Children’s Hospital in New York City. “The mouth doesn’t humidify the inspired air as well as the nose.” So, that arid air continues to dry out the membranes in nasal passages, airways and sinus passages, increasing congestion and discomfort.
How can you keep the air in your house from being bone dry in the winter? The most popular solution—and one that parents have turned to for decades—is to place a portable humidifier in a child’s room. But the solution is not an easy one, because there are many kinds of humidifiers to choose from.
Types of Humidifiers
- Cool-mist humidifiers do their job by releasing a spray of cool mist into the air. Ultrasonic humidifiers, which use high-frequency vibrations to break up water into fine particles, are a type of cool-mist unit.
- Warm-mist humidifiers emit a mist of warm water, generated when the unit boils water then cools it a bit before it is released.
- Vaporizers boil water and send it in the air as steam, rather than mist.
Dr. Gordon recommends that parents of children in his practice use cool-mist humidifiers to help clear their little one’s stuffy nasal passages. “If the temperature is 55 to 58 degrees, and the air is cool and moist, the mucous membranes work better. The cooler and moister your baby’s room, the better.”
He understands that parents often hesitate to put a chill in a sick child’s room, but he assures them that the cool air is really the healthiest. “Parents use warm-mist humidifiers because it makes them feel better,” he says. “But being cold does not make you sick.”
The benefit of warm-mist humidifiers and vaporizers is that when they boil the water, they kill any bacteria that may be swimming in the water. The boiling process reduces—but does not eliminate—the need to clean the unit daily.
Germs In the Mist
Adding to the confusion is the fact that, while each type of humidifier has its benefits, there are health risks associated with them. Any wet environment can harbor germs and cause mold to grow—and a humidifier is, by definition, wet.
With humidity, too much of a good thing is bad. “Humidity levels above 50 percent set up an environment ideal for the growth of mold and dust mites,” says Dr. James L. Sublett, MD, FAAAI, managing partner of Family Allergy & Asthma, a group of asthma and allergy specialists in Kentucky and Indiana.
If you see condensation forming on the windows, lower the humidity level. If you see mold or mildew starting to form around the windows, on the walls, or anywhere else in your child’s room, turn off the humidifier immediately. The mold can be much more dangerous than the stuffy nose you’re trying to alleviate.
The drawback of a cool-mist unit is that the water isn’t boiled and is more prone to breeding mold spores and bacteria, and spreading them throughout the room. Those particles can lead to further coughing as well as allergic reactions such as wheezing and skin problems.
However, warm-mist humidifiers, despite the boiled water that they use, are not germ free. “There are no germ-free vaporizers,” says Dr. Sublett. “Even in a hospital setting, it is impossible to sterilize a humidifying device.” Warm-mist humidifiers and vaporizers pose not only potential health risks, but also a safety hazard. The boiled water is very hot, as is the mist or steam that comes out of the unit. If you use a warm-mist unit, make sure that it is safely out of your child’s reach.
Eliminating Bacteria Problems
The solution to that problem is easy. Use the cleanest water you can find; distilled water is the best. Never leave water sitting in the humidifier when you’re not using it. Also, make sure to clean the unit thoroughly and regularly—at least weekly—with bleach or vinegar to kill bacteria and mold spores. And, just in case you don’t get rid of every germ in the system, place the humidifier away from your child’s bed, so that the mist and the germs in it don’t settle directly on your child.
You also can reduce—but not ever eliminate—the likelihood that your humidifier will grow bacteria or mold by adding an antibacterial agent, or “bacteriostat,” to the water. Typically, you add one capful of the solution per gallon of water in the tank. You must add the solution religiously or it won’t do any good, says Bill McTighe, an indoor air-quality specialist with Home Environmental, Inc.
Dr. Sublett does not encourage parents to turn on a humidifier at all, but instead recommends good hydration from the inside. He says to make sure your child drinks plenty of fluids, especially water. He also advocates saline-based nasal drops to ease congestion. The drops, available over the counter, soften mucus, allowing it to drain or be suctioned easily with a bulb syringe.
If you feel that your child would benefit from more humid air, but don’t want to use a humidifier, Dr. Loughlin suggests a simple, low-tech approach. Put a bowl of water in the room—on a radiator, if you have one. The water will evaporate into the air and increase the humidity with no electricity required.