Wrinkles, fine lines and pigmentation are inevitable skin woes that often appear as we age. While we like to place blame on getting another year older, the main culprit is photoaging — damage to the skin caused by exposure to sunlight and ultraviolet (UV) light. Responsible for 90 percent of visible changes to the skin, photoaging is a direct result of cumulative sun damage you’ve been exposed to throughout your life.
“Premature aging of the skin is caused by light exposure,” says Melanie Palm, MD, Medical Director of Art of Skin MD in Solana Beach, California. “This can also include visible (HEV) and infrared light, which are other parts of the light spectrum.”
Light is around us at all times, making sun damage a year-round concern for healthy skin. Chronological skin aging can’t be helped (it’s tough to fight time), but photoaging accelerates the process. The good news is that it’s completely preventable. We turned to Dr. Palm to explain the causes and symptoms correlated to photoaging and the treatments that can keep you out of the antiaging aisle just a little bit longer.
Breaking Down the Light Barrier
Skin is composed of three layers: the epidermis, or outermost layer; the dermis, or middle layer; and the subcutis, or bottom most layer. The dermis contains collagen, elastin and other fibers that support the skin’s structure. It is these elements that give skin its smooth and youthful appearance — and that are damaged by UV radiation.
The UV radiation that affects the skin is composed of two different types of waves, UVA and UVB. When UV rays hit the skin, they damage its DNA, and cells in the dermis scramble to produce melanin in the epidermis to prevent further damage. This is the process that gives you a tan, which is really just your skin attempting to block the radiation from penetrating your skin.
UVB rays are shorter than UVA rays, and are the main culprit behind sunburn. The UVA rays, with their longer wavelength, are responsible for much of the damage we associate with photoaging. UVA rays penetrate deep into the dermis, where they damage the collagen fibers. This damage causes increased production of abnormal elastin. The unusual amounts of elastin result in the production of enzymes called metalloproteinases. These enzymes, which rebuild damaged collagen, often malfunction and degrade the collagen, resulting in incorrectly rebuilt skin. As this process is repeated with daily UVA exposure, the incorrectly rebuilt skin forms wrinkles, and the depleted collagen results in leathery skin.
Beyond the Sun
While sunlight is the number one cause of skin aging, about 10 percent comes from HEV and infrared light. HEV, or high-energy (blue) visible light, which emits from the sun and devices such as your phone or computer and can be seen by the human eye. This light doesn’t stop when the sun goes down. Infrared light is invisible to the eye and rather is felt as heat, like in a microwave.
Fortunately, neither of these has been linked to skin cancer, but they have been shown to break down collagen and skin elasticity. In recent years, some research is focusing on the additional effects of these other light forms may have on the skin. According to a 2014 study in the journal Photodermatology, Photoimmunology & Photomedicine, non-UV solar radiation significantly contributes to photoaging and needs to be taken into consideration when formulating a skin-protective regimen.
The effects of photoaging can manifest in many ways. “Melasma, freckles, actinic keratoses and texture changes are all signs of photoaging damage,” says Dr. Palm. The type of damage one deals with, however, is unpredictable and dependent on the individual.
For example, sun exposure (and hormonal changes) can cause melasma, which is a condition causing grayish-brown patches to appear on skin. Actinic keratoses (AKs), or precancerous spots, directly correlate to chronic sun exposure, which can increase your chance of developing skin cancer. Textural changes in the form of deep lines, waxiness or a leather-looking appearance can lead to uneven, dull looking skin. Remember the cute freckles you got as kids? Those were actually warning signs from your body saying you’d had a lot of sun exposure. Broken blood vessels that exist as redness or blotchiness on the nose, cheeks or neck may resemble a slight burn and are another sign of sun damage.
Wearing sunscreen every day can do more than prevent skin cancer — it can prevent signs of photoaging as well. In fact, many people tout sunscreen for being their go-to antiaging weapon, and for good reason. Regular use has been shown to keep photodamage at bay for a longer period of time. Dr. Palm recommends a physical sunscreen (containing zinc oxide and/or titanium dioxide), which has a broader coverage for UVA rays. It should be at least SPF 30.
“Some sunscreens now contain DNA repair enzymes that help undo previous damage by using nearby undamaged DNA to fix the area,” says Dr. Palm. A 2017 study in the Journal of Drugs in Dermatology showed these products can enhance antiaging regimens and, more specifically, reduce risk of developing AKs.
If you’re already experiencing some of the above-mentioned signs of photoaging, you’ll also want to incorporate skin care products designed to reverse sun damage. Certain ingredients such as vitamin C and E and green tea are antioxidants that stabilize the skin and help brighten dark spots. An antiaging hero, retinol, used nightly, will boost cell turnover to create a healthy and youthful appearance.
“There’s really no reason for photoaging,” avows Dr. Palm, “We can keep skin looking good for decades if we just take care of it.”
Credit: Arielle Grabel, skincancer.org