Dry Skin - Common Skin Conditions: Skin Health

Content provided by the Faculty of the Harvard Medical School

Dry skin

Just about everyone has dry skin at some time in his or her life, but it becomes much more common with age. A tendency toward dry skin can be inherited, but experts estimate that at least 75% of people over age 64 have dry skin. Although you may take it for granted that skin becomes dry as a result of chronological aging, much of the loss of moisture is due not to aging, but rather to the cumulative effects of sun exposure. Sun damage results in thinner skin that doesn't retain moisture.

Over time, the production of natural oils in the skin also slows, and skin isn't as well lubricated as it once was. The outermost layer of the skin can be likened to a brick wall: The skin cells are stacked in layers with a "mortar" of keratin and natural oils that maintains the skin's suppleness. Just as a brick wall dries and crumbles with time and exposure to the elements, so, too, can skin become dry, cracked, and itchy. Some medical conditions, such as hypothyroidism, diabetes, and kidney disease, increase the likelihood of developing dry skin.

Treating dry skin with moisturizers

The first line of defense against dry skin is an effective moisturizer that softens and smoothes skin with water and lipids (fats). Some of these products attract water to the skin and seal it in, while others prevent skin from losing water by coating it with a thick, impermeable layer. One of the most effective products is petrolatum, also known as petroleum jelly. It's used in a number of moisturizers and ointments because it's inexpensive and stops water loss without clogging pores. Lanolin is another widely used ingredient. But despite their ability to soothe the irritation of dry skin, moisturizers can't prevent or reduce lines and wrinkles.

Petroleum jelly, although effective, isn't very popular as a moisturizer by itself because it feels greasy. And people with arthritic hands find such thick moisturizers difficult to apply. Moisturizing oils, such as mineral oil, are effective without being as greasy. Petroleum jelly and moisturizing oils contain no water. Because they don't add water, they're best used while the skin is still damp after bathing to seal in moisture, which prolongs their skin-softening effect.

Lotions and creams are emollients that contain basic ingredients of water and oil and can be used at any time to help add moisture to the skin at least temporarily. For commercial appeal, many have fragrance and color added. Lotions and creams are more popular than petroleum jelly or oils because they're less greasy and more cosmetically appealing. Lotions have a thinner consistency than creams because they contain more water. Most also contain an emulsifier to keep the product from separating. Humectants, including sorbitol and glycerin, are used to bind water to the skin and help it absorb moisture.

Six ways to prevent dry skin

Along with moisturizers, a few changes in lifestyle or your environment can help alleviate dry skin:

• Add moisture to the air with humidifiers or a pan of water set atop the radiator.

• In the shower or bath, use water that's lukewarm instead of hot; hot water can further dry the skin by stripping it of natural oils.

• Choose nondrying soaps that contain no abrasives or irritants. Super-fatted soaps or cleansing bars are less drying than regular, liquid, or antibacterial soaps.

• Instead of rubbing, pat your skin dry after you bathe.

• Apply moisturizer immediately to retain the water your skin absorbed while bathing.

• Wear soft fabrics that won't scratch or irritate the skin.

Last updated:	July 20, 2007