Ask Dr. K: Restore dry skin with the change of seasons

I was raised in Southern California, and the air was not particularly dry even in winter. As a result, I virtually never had a problem with dry skin — except after I stayed out in the sun too much.

When I came to Boston in my 20s, my young skin was exposed for the first time to long periods of really dry air in winter. Still, my skin never got dry until I entered my late 40s. I began to notice roughness, flaking, itching and cracking. That’s when I started to do the simple and inexpensive things I now recommend to you.

Skin moisturizers, which rehydrate the outermost layer of your skin and seal in moisture, are a good first step. Moisturizers contain three main types of ingredients. Humectants help attract moisture. Other chemicals — petrolatum (petroleum jelly), silicone, lanolin and mineral oil — help seal that moisture within the skin. Emollients, such as linoleic, linolenic and lauric acids, smooth skin by filling in the spaces between skin cells.

In general, the thicker and greasier a moisturizer, the more effective it will be. Some of the most effective are petroleum jelly and moisturizing oils, which prevent water loss without clogging pores. Because they contain no water, they’re best used while the skin is still damp from bathing, to seal in the moisture. Other moisturizers contain water as well as oil. These are less greasy.

Here are some additional ways to combat dry skin:

— Use a humidifier.

— Limit yourself to one five- to 10-minute bath or shower daily.

— Use lukewarm water rather than hot water. When hot shower (or bath) water evaporates from your skin, it takes away more moisture.

— Minimize your use of soaps. If necessary, choose moisturizing preparations, or consider soap-free cleansers.

— Steer clear of deodorant soaps, perfumed soaps and alcohol products.

— Avoid bath sponges, scrub brushes and washcloths.

— Pat or blot (don’t rub) the skin when toweling dry.

— Apply moisturizer immediately after bathing or after washing your hands.

— Don’t scratch dry spots. Most of the time, a moisturizer or cold pack can control the itch.

— Use fragrance-free laundry detergents and avoid fabric softeners.

— Avoid wearing wool and other fabrics that can irritate the skin.

Chronically dry skin is chronically irritated skin. It is more likely to develop blotchy colors and red, chapped areas. Keeping your skin moist will improve its appearance.

Dr. Anthony L. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.