Dry Cycle : New Moisturizers Replenish the Body’s Natural Protection Against Parched Skin

BY THE END of January, the effects of winter are etched only too clearly on many Southern California faces. Changes in humidity and dramatic differences between indoor and outdoor temperatures leave complexions lined, flaky and rough. Even people with oily skin may suffer from parched skin and turn to moisturizers for relief.

But instead of reaching for old-fashioned moisturizers that are thick and greasy, or even the lighter creams and lotions of the past decade, people with dry skin are seeking longer-lasting solutions. In response, cosmetics companies are introducing moisturizers formulated to combat the causes of moisture loss.

Until recently, those causes have been misunderstood. For instance, an American pharmaceutical company surveyed 440 consumers and 220 dermatologists and found that while most of the doctors considered aging to be the major cause of dry skin, most of the consumers listed the sun as the main offender. Ironically, the laymen, not the experts, appear to be on the right track.

“Associating dry skin with aging is a major fallacy,” says Peter Elias, vice chairman of dermatology at the UCSF School of Medicine. “There is no relationship. Dry skin can happen at any age.”

It’s easy to understand how rough, flaky skin would be so readily linked with aging. After all, the body’s natural oil production does slow somewhat over the years. But, says James Leyden, professor of dermatology at the University of Pennsylvania School of Medicine, “the majority of people produce approximately the same amount of oil. The outer layers of the skin are prime (targets) for abuse, however, and that abuse may cause dry skin, regardless of age.”

The outermost layers of skin cells, technically known as the stratum corneum, were once thought to be inactive and unnecessary, but doctors have discovered that they determine the moisture content of the skin. Fats and proteins serve as a kind of mortar that bonds the layers of cells together. An unbroken stratum corneum serves as a protective barrier against the environment and seals in moisture.

Cold temperatures, low humidity and increased sun exposure deplete the fats between the cells, causing the most damage to the protective barrier. “The stratum corneum tends to crack on people with dry skin, and evaporation occurs very quickly,” Leyden says. New moisturizers such as Estee Lauder’s Time Zone and Biotherm’s Aqualogic are aimed at replenishing the fats, or lipids, to keep the stratum corneum intact.

“It is possible to replace those lipids to help correct an abnormal outer layer of the skin,” says Santa Monica dermatologist Nicholas Lowe, a professor at the UCLA School of Medicine. He notes that the test of an effective moisturizer is how long it keeps the skin moist: “A superior moisturizer can have a cumulative, more lasting effect than products that just sit on the skin, temporarily holding moisture in.”

“By ‘regluing’ those skin cells together, moisture stays in the skin where it belongs,” says Walter Smith, Lauder senior vice president of research and development. “This keeps the stratum corneum in better condition, allowing it to get stronger over time, so you actually have long-term benefits.”

Keeping skin soft and pliable is easier with lighter creams that can penetrate the stratum corneum and distribute proteins and fats throughout the protective layer. Old moisturizer formulas need to be viscous to support heavy fats and proteins, but new ones make use of ingredients whose smaller molecular structures allow them to be mixed with much lighter emollients. Some, such as Prescriptive’s Simply Moisture and Rene Guinot’s Hydrazone, are so light that manufacturers say even women with oily skin can use them without fear of clogging pores.

For the remainder of winter, the season for peak moisturizer sales, Lowe suggests that consumers look for products that perform dual functions. “It’s no longer enough for a product to be an effective moisturizer--it should also contain a sunscreen,” he says. Time Zone, Schering’s Complex 15 and Stendahl’s Hydro Extreme combine sun protection with moisturizing ingredients.

So, while dermatologists could once recommend only messy petroleum jelly as an effective moisturizer, the list of alternatives has grown. “Today, many of the new products make logical sense,” Elias says. “We’ve come a long way from Vaseline.”

Stylist: Mindy Hahn; hair and makeup: Max McBeth / Celestine / Cloutier; model: Caren Goldstein / eastwest PRIMA; mirror courtesy of La Maison Francaise Inc.