The Best Protection Against Photoaging

Photoaging refers to the damage that is done to the skin from prolonged exposure, over a person's lifetime, to UV radiation. Most of the skin changes that occur as we get older are accelerated by sun exposure. Examples of skin changes from photoaging include:

• Dark spots
• Wrinkles
• Droopy skin
• A yellowish tint
• Broken blood vessels
• Leathery skin
• Skin cancers

Protection Against Photoaging
"Photoaging" is the term that describes damage to the skin caused by intense and chronic exposure to sunlight. The visible effects of photoaging are fine wrinkles, mottling and pigmentation of the skin, and skin roughness—changes that are usually associated with chronologic aging (calendar years). But, photoaging is not a good indicator of chronologic age; it just makes a person to look older than his or her chronologic age. The three approaches to counter photoaging are:

1. Avoid the midday sun
2. Prevention by use of photoprotective agents—sunscreen and clothing
3. Skin rejuvenation treatments (Click on Cosmetic Treatment)

Photoprotection is the use of physical and/or chemical agents to prevent the skin-damaging effects of ultraviolet (UV) radiation in sunlight. Physical agents are clothing, umbrellas and parasols, awnings and tents that protect you from sun when you are outdoors. 

Chemical agents are sunscreens you apply to your skin.

The effects of UV radiation on the skin are related to the intensity and duration of UV exposure. 

Avoiding intense, chronic exposure to solar radiation—for example, avoiding activities such as sun bathing—is one important way to protect against photoaging. 

Photoaging can be minimized by avoiding sun exposure between 10 AM and 4 PM. If you cannot avoid sun exposure between these peak hours of UV intensity, use sun-protective measures such as wearing a broad-brimmed hat and long-sleeved sun-protective clothing. 

You also need a broad-spectrum sunscreen with SPF 30 or higher if you are going to be exposed to sunlight for more than 20 minutes. An important point to remember: Even on cloudy days, 80 percent of the sun’s UV rays reach the ground. A cloudy day is not a reason to skimp on photoprotection.

Available topical retinoids include prescription tretinoin (Retin-A^®), adapalene (Differ en^®), and tazarotene (Tazorac^®) and over-the-counter Retinol^® and Ret in ol-A^®. These drugs are derivatives of vitamin A which have anti-aging properties. Topical tretinoin was first observed to ameliorate the clinical signs of photoaging by Cordero (1983) and Kligman, Grove, Hirose, and Leyden (1986). The first double-blinded, randomized, vehicle-controlled clinical trials investigating the use of tretinoin for photoaged skin were performed in the late 1980s. In these studies, investigators found that surface roughness, dyspigmentation, and fine wrinkles demonstrated the most improvement with topical tretinoin therapy in the first 4 to 10 months of therapy (Weiss et al., 1988). Because epidermal changes seen early in therapy reverted to baseline, the wrinkle-improving effect of tretinoin was presumed to be due to effects on the dermis. In studies, topical tretinoin increased collagen type I in photoaged skin (Griffiths et al., 1993; Talwar, Griffiths, Fisher, Hamilton, & Voorhees, 1995). It is common and predictable for patients to develop a retinoid dermatitis characterized by erythema and scaling after starting a retinoid. With time and continued use, this dermatitis improves. A patient may use topical tretinoin as part of a daily and ongoing program to reverse the signs of clinical photoaging. Topical tretinoin is typically prescribed as a 0.05% or 0.1% cream, and for patients more sensitive to the effects, lower strengths can be used (0.02%, 0.025%). Tretinoin can be used indefinitely. There are no true contraindications to its use, though some patients are not able to tolerate the accompanying retinoid dermatitis.

Cosmeceuticals are agents that are marketed as cosmetic products, contain biologically active ingredients, and are available without a prescription. Drugs exert a biologic effect, are dispensed by prescription, and are regulated by the U.S. Food and Drug Administration. Cosmeceuticals do not undergo the rigorous testing required for drug approval, and there are few clinical controlled trials of these products. In fact, most of the work supporting their use is in vitro or small, open-label, industry-sponsored trials. The cosmeceutical industry is huge and future projections estimate that it will exceed $16 billion by 2010 (Choi & Berson, 2006). Cosmetic products containing peptides, antioxidants, and botanicals are examples of cosmeceuticals. A complete review of cosmeceuticals is beyond the scope of this article, so only select ones will be mentioned.

Peptides are amino acid chains that are fragments of large proteins such as collagen. Pal-KTTS is a collagen peptide fragment, and there is evidence in wound healing that it may penetrate into the dermis and stimulate collagen production (Katayama, Armendariz-Borunda, Raghow, Kang, & Seyer, 1993). Pal-KTTS is marketed as Matrixyl^[99] (Sederna, France) and is an ingredient in a number of cosmeceuticals. A tripeptide-copper complex can increase collagen in wounds and is an ingredient in a number of cosmeceuticals such as Procyte GHK-copper peptide (Maquart et al., 1993).

Antioxidants are molecules that work in the skin to reduce ROS, which are generated by UV damage and lead to breakdown of collagen. There is much interest in the use of antioxidants both orally and topically to combat aging skin, but there are few published studies on the efficacy of these agents. There is reason to be optimistic, as preliminary studies demonstrate that certain antioxidants may exert an anti-aging effect by preventing and even reversing sun damage. 

Idebenone is a synthetic analog of Coenzyme Q 10 with potent antioxidant activity; it reduces skin roughness, increases skin hydration, reduces fine lines, and was associated with an improvement in overall global assessment of photoaged skin (McDaniel, Neudecker, DiNardo, Lewis, & Maibach, 2005). Topical vitamin C 5% cream applied for 6 months led to clinical improvement in the appearance of photoaged skin with regard to firmness, smoothness, and dryness compared to vehicle (Humbert et al., 2003). Topical vitamin C stimulates the collagen-producing activity of the dermis (Nusgens, Humbert, Rougier, Richard, & LapiE8re, 2002).

Protect the hands from photo-aging