Photoaging Causes and Treatment

Photoaging refers to skin damage caused by prolonged sun exposure, specifically UVA and UVB rays, and can lead to skin cancers. Most of the skin changes that occur as we age are accelerated by sun exposure.

Skin is composed of three layers: the epidermis, the dermis, and subcutaneous tissue. The dermis contains proteins including collagen, elastin and other important fibers that affect the skin's strength and elasticity, and are responsible for skin's smooth, youthful appearance. UV radiation (UVR) damages these important proteins, leading to photoaging.

You probably have a pretty good idea what photoaging looks like. You may have looked at magazine photos, seen an acquaintance, and commented that the person had obviously had too much sun exposure (and perhaps smoked as well which causes yet further damage to the skin.)

Signs of Photoaging can include:

• Wrinkles
• Drooping skin (inelasticity)
• Dark spots ("age spots")
• Broken blood vessels (telangiectasias)
• A yellowish tint to the skin
• Leathery texture to the skin
• Mottled pigmentation
• Easy bruising

UVR is made up of UVA and UVB rays. In general, UVB rays burn, while UVA rays age the skin, but there is considerable overlap in the damage these rays cause.

UVA rays have longer wavelengths and can deeply penetrate the dermis. The rays damage existing collagen, which causes increased elastin production. Such abnormal amounts of elastin lead to the production of enzymes known as metalloproteinases that repair damaged collagen. However, these enzymes usually end up causing more harm to the collagen than good by incorrectly restoring the skin. As the skin is exposed to UVA rays on a daily basis, this process keeps repeating, resulting in wrinkles and leathery skin.

UVA exposure also causes fine lines and wrinkles around the eyes, mouth, and forehead, as well as age spots, or liver spots. An age spot is a spot of pigmentation caused by sun exposure. They appear not only on the face but on the rest of the body, including the hands, the arms, the chest, and the back.

While many elements of photoaging are unavoidable, visible signs of aging can be prevented. Apply sunscreen of at least SPF 30 every day (using only products which protect against UVA as well) to areas that are exposed to the sun: the face, neck, chest, hands, arms, legs, etc. In addition to preventing photoaging, daily application of sunscreen can also reduce current signs of photoaging, as well as the risk of developing skin cancer. Due to widespread vitamin D deficiency in developed countries, and the consequences of deficiency, some dermatology organizations are recommending a small amount of sun exposure without sunscreen (and you will be hearing more about this.) The key word here, however, is small. Often 10 to 15 minutes in the sun is plenty of time to absorb a good, healthy dose of vitamin D before you apply your sunscreen.

Perhaps the most important thing you can do to reduce the photoaging of your skin (other than reducing your sun exposure) is to choose a sunscreen which protects you against UVA rays. That said, it's not that easy. In fact, you are more likely to find a product which advertises itself as broad coverage but does not protect you from UVA rays at all.

In order to find a sunscreen which protects against UVA rays, it's important to not just look at the title on a package but to read the list of ingredients. Learn about the sunscreen ingredients which protect against UVA rays, including the pros and cons of different products, plus how long the sunscreen will last between applications.

With the advent of sunscreen, we often forget that there are simple ways to reduce skin damage due to sun exposure. Since there isn't a perfect sunscreen which can protect you from all damaging rays, remember to:

• Avoid sun exposure when the sun is strongest - usually between 10 am and 2 pm
• Use umbrellas and shade
• Wear a wide brim hat to protect your face
• Wear protective clothing, for example, loose-fitting clothes with an SPF factor

Finally, don't forget your eyes. Being out in the sun without sunglasses may accelerate macular degeneration, the leading cause of blindness with age.

The gold standard for treating photoaging, especially mild to moderate photoaging, has been vitamin A products such as retinol and Retin A treatment. Over-the-counter products may be effective, but prescription medications (Retin A and Differin) are much more concentrated. These medications were first used for acne and then found to reduce wrinkling, especially fine lines, and facial wrinkles. Retinoids work by increasing cell turnover and can take a few months before you will notice a change. Some people develop redness and a rash when a higher concentration product is used, but a slow increase in dose can often eliminate this reaction.

There are also many dermatological advancements that treat photoaging, namely light-based technologies including photodynamic therapy, intense pulsed light, and laser therapy:

• Photodynamic therapy is a technique that involves applying a light-sensitizing medicine to the skin. Once the medication has penetrated the skin, the affected area is exposed to a light that activates the medication, promoting collagen growth that gives skin a more youthful, supple appearance.
• Intense pulsed light is a light therapy technique that is effective in diminishing the appearance of uneven pigmentation and broken blood vessels over a series of sessions.
• Laser therapy can treat a variety of skin issues depending on the wavelength of light applied to the skin. Different wavelengths are used for minimizing blood vessels, treating age spots, reducing wrinkles, removing hair, etc.

The Bottom Line

Keeping your skin young and healthy appearing means practicing caution in the sun. Yet for those who had excess sun exposure in years past, there are some treatments that do not cure but can reduce age-related skin damage. Remember that what causes wrinkling, also causes skin cancer.