Treatments abound for crow's feet and fine lines, but there's plenty of confusion about what works and what's hogwash. Now comes some clarity.
Over the past decade, University of Michigan researchers have focused on the mechanisms behind aging skin and have emerged with a better understanding of how best to tame the process—without Botox or plastic surgery. After analyzing several dozen of their studies, the team reported last month that three treatments definitely rejuvenate skin: topical retinoic acid, carbon dioxide laser resurfacing, and injections of cross-linked hyaluronic acid. "These three, as far as I'm concerned, are the ones where the evidence is quite solid," says senior author John Voorhees, chair of the department of dermatology at the University of Michigan's medical school (who has no financial ties to the manufacturers of the treatments studied).
Why do they work? All three are able to replenish some of what skin loses with time: collagen. Wrinkles form as collagen breaks down, which signals the cells that secrete it to stop doing so. Age and sun exposure are triggers. But this cycle isn't irreversible, says Voorhees. Treatments can sweep away the old, splintered collagen, and fool cells into making more. Since collagen has a half life of 15 years, once it's laid down, lots will last, he says. "What we're trying to say is that you actually have to do something to the skin to make it repair and rejuvenate," says Voorhees. "You can't expect magically to put on a potion which will stimulate the repair process deep in the skin. It doesn't happen."
An informal survey of other dermatologists found agreement that these approaches work, along with a few alternatives:
Retinoic acid. Derived from vitamin A (though not the kind found naturally in carrots and other orange-red vegetables) creams that contain retinoic acid require a prescription and work by gradually stimulating the formation of new collagen. For best results, Voorhees recommends creams with .025 or .05 percent tretinoin (another name for retinoic acid).
Certain over-the-counter products have similar wrinkle-smoothing effects, like those containing retinol, which is converted to retinoic acid in the body. However, many of these products are useless, warns Voorhees, because they contain infinitesimal amounts of the key ingredient. Though there's no precise way to tell a dud from a winner, cosmetic dermatologist Zoe Diana Draelos, editor of the Journal of Cosmetic Dermatology, advises checking labels to see where retinol falls in the lineup: If it's among the last five ingredients listed, it's probably there to preserve the product; if it's listed higher up, it's probably there in skin-benefiting concentrations.
Some caveats: Even with prescription-grade products, don't expect more than modest improvement, which can take between six weeks and six months to notice. You'll probably experience some flaking, skin tightness, and increased sun sensitivity, says Voorhees. These creams are best for small lines around the eyes and upper cheeks, not for deep folds, adds Draelos, though her wrinkle-free patients often apply them pre-emptively. Because vitamin A can cause birth defects, she says pregnant women should avoid these products.
Instead try topical vitamin C, which microscopic studies have shown can also boost collagen, says New York-based dermatologist Arielle Kauvar, who specializes in the treatment of aging skin. Whether in cream, serum, or gel form, it's primarily used because of its antioxidant properties, which inhibit free radical damage from the sun, she says. While formulations don't require a prescription, potency can be tough to gauge. Effective products would most likely contain 10 to 20 percent L-ascorbic acid (a type of vitamin C), she says, and come in opaque containers: Exposure to light saps their strength over time. "It's a preventive measure," she says, "but it has some restorative benefits."
Carbon dioxide laser resurfacing. For those desiring more drastic results, carbon dioxide laser resurfacing has been shown to be effective, says Voorhees. "You get nice, new skin," he says, "but I personally don't recommend it because it's so invasive."