Beautiful skin is never just skin deep. What you massage into your skin is likely to be absorbed into your bloodstream, and what you subject your body to shows up on your skin. Clear, radiant skin is a mark of vitality while good skin contributes, in turn, to good health.

That's because your skin is more than a body wrapper. It's your body's largest organ, and the trillions of cells that compose it serve as your first line of defense against microbial invasion and help regulate your body temperature. Skin covers an astonishing 19 square feet of area, weighs in around seven pounds and is teeming with sweat glands, sebaceous glands, hair follicles, blood vessels, heat and cold sensors and nerves.

How smoothly, easily and flexibly your skin performs its many duties and how well it looks has a lot to do with your health.

Those in search of the per-feet complexion will be delighted to know that nature turns out an entirely new epidermis every 28 days, but generally, it takes longer than that to clear up all your skin problems. In addition to the time it takes for skin to manifest bodily dysfunction--a stage in which your skin might look worse--it takes time to bring your body systems into balance.

Take It Off
The big cosmetic companies don't want you to know it, but those who use no products at all often boast better skin than those who buy every wonder cream that hits the market. The reason is that the average consumer is coating her face with petroleum--or worse.

Propylene glycol, for instance, is commonly used in cosmetics to hold moisture and promote skin elasticity. "But in high concentrations, it can be irritating to people with sensitive skin," says Mike Helman, who is in charge of product testing at Revlon and Almay.

Mineral oil, another prevalent component, is attractive to cosmetic manufacturers because it is cheaper and more stable than vegetable oils, but it clogs the pores, causing allergic reactions such as hives and rashes. Isopropyl alcohol, isopropyl myristate, sodium lauryl sulfate and triethanolamine can also cause problems.

"People come to me with severe allergic skin reactions caused by cosmetic chemicals that strip the skin and cause breakouts," says Zia Wesley-Hosford, an esthetician and cosmetologist.

The picture is a lot prettier with products labeled "natural," but these cosmetics may contain binders, emulsifiers, artificial colors and fragrances that irritate the skin. For more on this subject, refer to A Consumer's Dictionary of Cosmetic Ingredients, by Ruth Winter (Crown, 1994).

Department store "natural" skincare products, such as Clarins, contain artificial colors, fragrances and mineral oil. Many natural food store brands do not, but you might want to scan the label for multisyllabic ingredients that sound chemical in origin. When in doubt, contact the manufacturer.

If you suffer from sensitive skin, acne or other persistent problems, don't hide under a blanket of foundation and concealer--you might worsen your condition. Your best bet is to go au naturel and lead a healthy lifestyle. You don't want to go without makeup? Then buy or make natural products that don't contain any of the previously mentioned culprit chemicals and monitor the results very carefully.

Herbalist Rosemary Gladstar of East Barre, Vt., makes her own skincare products to guarantee the quality of what she puts on her face. According to Gladstar, the cosmetics on store shelves can damage our skin because they often sit around for months, dry out and become rancid.

Put It On
Many women with beautiful skin use remedies as simple as sesame oil for cleanser and apple cider vinegar mixed in olive oil for a moisturizer.

Don't care to walk around smelling like a Caesar salad? Add one drop each of the essential oils of lavender, rose and/or myrrh to a generous teaspoon of almond or olive oil in the palm of your hand and massage it in.

"My favorite skincare product in the world is raw honey," says Gladstar. "There's nothing better to make dry skin look lively. Add a few drops of essential oil of lavender or rose to it and gently massage into temples, cheeks and chin. This concoction wakes the face up by stimulating blood circulation."

For oily or acne-prone skin, Gladstar recommends a mask of volcanic green clay, available in most natural food stores. "It has minerals that draw out toxins," she says. If you have very sensitive, fair skin, she recommends white kaelin clay.