Mayo Clinic: Humidifiers can ease skin, breathing symptoms

Dry sinuses, bloody noses and cracked lips: Humidifiers are often used to soothe these familiar problems caused by dry indoor air. And if your child has a cold, a cool-mist humidifier may ease a stuffy nose by adding moisture to the air.

But humidifiers can make you sick if they aren’t maintained properly or if humidity levels stay too high. If you use a humidifier, check the humidity levels in the room where it is used and keep your humidifier clean. Mold or bacteria can grow in dirty humidifiers. If you have allergies or asthma, talk to your health care provider before using a humidifier.

What are humidifiers?

Humidifiers are devices that release water vapor or steam. They boost the amount of moisture in the air, also called humidity. Types of humidifiers include:

Humidifiers only add moisture to the air. You can’t use them to breathe in products such as essential oils for aromatherapy.

Ideal humidity levels

Humidity varies depending on the season, the weather and where your home is. In general, humidity levels are higher in the summer and lower in the winter. It’s ideal to keep the humidity in your home between 30% and 50%. Humidity that’s too low or too high can cause problems.

How to measure humidity

The best way to test humidity levels in your home is with a hygrometer. This device looks like a thermometer. It measures the amount of moisture in the air. When you buy a humidifier, think about getting one with a built-in hygrometer. This is called a humidistat. It keeps humidity within a healthy range.

Humidifiers, asthma and allergies

If you or your child has asthma or allergies, talk to your health care provider before you use a humidifier. There are some risks.

Cool-mist humidifiers may ease a child’s stuffy nose during a cold. But heated humidified air doesn’t seem to have the same result.

Also, mist from a dirty humidifier can trigger or worsen asthma and allergy symptoms. So can the growth of allergens caused by high humidity.

When the air’s too damp: Dehumidifiers and air conditioners

Just as air that’s dry can be a problem, so can air that’s too moist. When humidity gets too high, which can be common during summer months, it’s a good idea to take steps to lower indoor moisture. You can lessen humidity by using:

Keep it clean: Dirty humidifiers and health problems

Dirty water tanks and filters in humidifiers can grow bacteria and mold. This mainly can cause problems for people with asthma and allergies. But dirty humidifiers can be trouble even for healthy people when they release mist or steam tainted with bacteria or fungi into the air. That may trigger flu-like symptoms or even lung illnesses. Evaporators and steam vaporizers may be less likely to release airborne allergens than may cool-mist humidifiers.

Tips for keeping your humidifier clean

To keep humidifiers free of harmful mold and bacteria, follow the instructions suggested by the device maker. These tips for portable humidifiers also can help:

Other ways to deal with dry air

If you don’t have a humidifier, you can take simple steps to ease some problems tied to dry air:

Ease a dry nose with a saline spray or rinse. Saline is a mixture of salt and water that may help moisturize dry nasal passages. You can buy a bottle of saline nose spray off the shelf. Or you could use a bulb syringe, squeeze bottle or a device called a neti pot to pour saline into your nostril. Some people make their own saltwater mixture at home. But you have to use water that’s distilled, sterile, filtered or boiled and then cooled. It’s not safe to rinse your nose with water straight from the tap. It can cause a serious brain infection that could lead to death.

Help soothe a sore, dry throat during a cold. Gargle with warm saltwater a few times a day. In general, mix a quarter teaspoon of salt with a half cup of water. Spit it out when you’re done gargling. It also helps to sip warm tea and drink plenty of water to stay hydrated.

Keep skin moist. Stay away from taking long, hot showers or baths. Limit them to 5 to 10 minutes and use warm water, not hot. If your skin is often dry, think about washing with soaps that are labeled fragrance-free.

Right after you bathe, pat dry and put on an ointment or cream. This helps lock in moisture. You can use cream or ointment after you wash your hands or face too. If your lips get dry and cracked, use lip balm.

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