Look 7 Years Younger

Step 2: Smooth Lines with Retinoids

Why this works: In studies dating back over the past 20 years, they have been shown to help soften the look of fine lines and brown spots by increasing collagen production and normalizing skin-cell activity. "These vitamin A derivatives have a better-established track record than any other wrinkle-reduction creams," says Dr. Glogau. Even the milder, nonprescription-strength retinol may reduce the effects of chronological aging — albeit more gradually. When University of Michigan researchers applied a .4 percent retinol lotion to one of the study participants' upper inner arms as many as three times a week for 24 weeks, skin biopsies revealed that that arm had more of the building blocks that make skin smooth and resilient than the untreated arm.

What to try: The biggest challenge with retinoids is dealing with the potential side effects, such as redness and peeling skin. Your skin will, however, build up a tolerance, usually within six to 12 weeks. Retin-A is still the gold standard in prescription strength, though there are several less-irritating options — costing $100 per tube on average — including Retin-A Micro, Differin, Avage, and Tazorac. Researchers continue to seek ways of making retinoids more tolerable; one theory currently being tested at the University of Michigan is that using an ultra-mild facial cleanser and moisturizer will help calm the irritation. (The study findings are still a few years away.) Dermatologists also suggest you ease into using one: Apply a pea-size amount at night (sun exposure makes retinoids less effective), and try it every second or third night until your skin handles it better. If that's still too irritating, go with an over-the-counter retinol. These formulas are less potent, but are still effective. Try L'Oréal Paris Advanced Revitalift Deep-Set Wrinkle Repair Night Creme ($20, drugstores) or DermaDoctor Poetry in Lotion Intensive Retinol 1.0 ($75, Sephora).

Years younger: 6-7. You should start to see an improvement in a matter of weeks with a prescription formula, but don't stop there. "Keep using it," says Dr. Dover, who claims he can always spot a woman on a prescription retinoid because her skin looks "too good" for her age. Over-the-counter retinol converts to the active form, called retinoic acid, at a lower concentration — but the benefits will start to show up after a few months if you stay with it.

Step 3: Load Up on Antioxidants

Why this works: Antioxidants act as scavengers that neutralize free radicals — the particles that, in skin, cause sun damage and wrinkles, and can lead to skin cancer. They can also help protect against damage from environmental assaults like pollution and smoking, says Dr. Hirsch. Though there is still some debate about whether they can reverse sun damage, at the least they deliver modest skin brightening, says Dr. Dover, since better-protected skin appears more even-toned.

What to try: Some foods are loaded with antioxidants that are beneficial to the body overall, "but most people don't eat enough of them to benefit skin," says Dr. Hirsch. She recommends ingesting them and applying them topically. Look for vitamins C and E, pomegranate, idebenone, soy, green tea, niacinamide, and coenzyme Q10 in the top half of a product's ingredient list to get the most benefits from these often-pricey potions. Try Vichy Liftactiv CxP Bio-Lifting Care ($43, drugstores) or Desert Essence Organics Age Reversal Pomegranate Face Serum ($15, Whole Foods).

Years younger: 1-2. If your skin immediately radiates youthfulness after slathering on an antioxidant-rich cream, thank your moisturizer; antioxidants won't work that fast. You have to keep using them for five or six months, says Dr. Dover, to see the benefits. After that time, not only should your skin tone be more even, but some of the fine lines may smooth out, and drier-looking skin will appear revitalized.

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