Breath of Fresh Air: Feature Articles

Chapter 31: Should I run a humidifier in the winter?

The cold air of New England winters lacks moisture. Our skin, mouth, and nasal passages often feel uncomfortably dry in this low humidity environment, and nosebleeds become more common with drying of the membranes lining the nose.

Nonetheless, for persons with asthma who are allergic to dust mites — and that represents nearly half of adult persons with asthma — drier is better during the winter. The dust mite grows best in moist climates — when the relative humidiy is between 50-80%. Running a humidifier during the winter is like feeding the dust mites and may worsen your allergic exposure. In addition, there is always the concern that the humidifier may become contaminated with living organisms that are then spread into the air as a fine mist for you to breathe, with potential harmful effects.

If you do run a humidifier, wash it periodically with a dilute solution of bleach to prevent growth of mold.