Winter takes a harsh toll on skin: Your complexion looks duller, your cheeks are dry and chapped, and maladies such as canker sores may flare up. So it's more critical than ever to treat skin with gentle ingredients and products that lock in your skin's natural moisture. Take some time this winter to give your face the nurturing it needs.

Tiny flakes of dry skin trap the light rather than reflecting it, making skin appear dull. Though your first impulse may be to slather on moisturizer, first you need to remove those dead skin cells with an exfoliant. Just be gentle -- you want to lift off the dead cells, not irritate the fragile barrier. Next, apply a cream that will hydrate the new cells and plump and brighten dried-out skin. For an even bigger moisture boost, put lotion on after leaning over a sink of warm water -- the air just above the surface of the water is super-hydrated and will add moisture to skin.

Look closely and you'll see that chapped skin actually has tiny fissures in the top layer. That's partially due to a lack of essential fatty acids (EFAs) in the body, which can lead to scaly dermatitis. To heal the fissures, cleanse gently and apply moisturizer directly afterward, to form a barrier that will help the skin stay hydrated. To avoid stripping the skin of its natural oils, wash your face only at night and just splash it with water in the morning. To boost EFAs, try supplementing. Dry and itchy skin may improve with a tablespoon of high-quality flaxseed or fish oil capsules taken daily for a few months.

Winter invites skin conditions such as rosacea, seborrheic dermatitis, eczema, and flushing. The change in temperature and dry indoor air mean your skin loses water; these conditions, which are aggravated by dryness, flare up. Anti-inflammatory antioxidants like green tea and vitamin C can help calm things down. To maintain your skin's natural barrier, use creamy cleansers that don't dry it out further and simple moisturizers with emollients and humectants such as glycerol. If you tend to break out, look for lightweight lotion.

If you're cursed with canker sores -- little mouth sores that seem to be more common in winter months -- a little licorice might help. In a study, researchers gave licorice-laced adhesive patches to 23 adults suffering from canker sores. Seven days after application, sores grew significantly smaller and less painful, while study members who'd received no treatment saw their sores increase by 13 percent.

To cure your own canker sores, try using a deglycyrrhizinated-licorice-based mouthwash or gel four times daily. If you can't find either product at your local natural foods store, steep a tablespoon of dried licorice root in a cup of simmering water for 15 minutes. Strain, let cool to room temperature, then rinse your mouth with the tea.

In blustery winter weather, lips get dry, flaky, cracked, and generally uncomfortable. "That's because lower humidity and colder temperatures dry out skin, and lips are part of the skin system," says Elizabeth Hale, clinical associate professor of dermatology at New York University School of Medicine. She suggests the following tips for maintaining soft and healthy lips.

We've all heard it before, but it bears repeating: Wear a good lip balm, and try not to lick your lips, which can cause them to lose moisture, making the problem worse, Hale says. Look for products with conditioning ingredients (such as petrolatum) as well as sunscreen (such as octinoxate). Don't rely on glosses, which actually attract sun. And use a thicker, more emollient product (such as the kind sold in a squeeze tube) to help repair and soothe lips overnight.