Photoaging
Photoaging

Photoaging is premature aging of the skin caused by repeated exposure to ultraviolet radiation (UV), primarily from the sun but also from artificial UV sources. Photoaging differs from chronologic aging: the damaging effects of UV rays – from the sun or artificial tanning sources – alter normal skin structures.

Lifetime exposure to sunlight is a key risk factor.

  • spider veins on the nose, cheeks and neck
  • various pigmented spots, such as freckles, solar lentigines (known as age or liver spots), and uneven skin colour
  • general loss of skin tone in sun-exposed areas
  • with continued sun exposure over several years, wrinkles around the eyes and mouth increase in number and become deep creases; forehead frown lines set in and are visible when not frowning
  • red, rough scaly spots called actinic (sun-related) keratoses may appear; these may be precancerous and require treatment
Where does photoaging appear?

Photoaging appears on the most visible parts of the body — face, neck and back of the hand. These areas often receive significant sun exposure. In women, the exposed upper chest is another area where photoaging is seen. The lips can also show signs of excessive sun damage.

UVB radiation penetrates the epidermal – outer – layer of the skin. It damages DNA in this layer and causes other changes in skin cells. This may result in early signs of photoaging, and over time precancerous cells and skin cancers may develop.

UVA radiation, while also damaging the epidermis, penetrates deeper into skin, to the level of the dermis. UVA not only harms epidermal cells, it also damages collagen and elastin, which make up the structure of the dermis and keep skin resilient. Blood vessels can also be harmed.

How much sun exposure causes photoaging?

Your skin type and the amount of unprotected sun exposure you get will determine risk. Fair-skinned people with blond or red hair and skin that usually burns with sun exposure are at greatest risk. Those who spend extensive periods in the sun through outdoor work or recreation also fall into the high-risk group. Darker-skinned people show fewer signs of photoaging, although the skin can become mottled and there may be wrinkling.

Photoaging can begin in the teen years or early 20s. Using UV light technology, areas of excess epidermal pigment (seen as freckle-like, dark spots) lying just below the skin’s surface are revealed.

Normal versus photoaging?

On sun-exposed skin, up to 90 per cent of aging is due to the sun’s harsh effects on skin. Compare skin on an area rarely exposed to that on the face to see the difference in tone, colour and texture. The natural aging process is dependent on time and genetics, and is unchangeable. However, photoaging can be avoided with good sun protection habits.

The Fitzpatrick skin type classification, based on a person’s reaction to sun exposure, helps you identify risk based on your skin type and reaction when in the sun.

Fitzpatrick skin typing

Skin type is often categorized according to the Fitzpatrick skin type scale, which ranges from very fair (skin type I) to very dark (skin type VI).

Type I —   always burns, never tans
Type II —   usually burns, then tans
Type III —   may burn, tans well
Type IV —   rarely burns, tans well
Type V —   very rarely burns, tans well, brown skin
Type VI —   very rarely burns, tans well, very dark skin

The three main factors that influence skin type are:

Genetic disposition  Skin type is determined genetically and is one of many aspects of overall appearance, which also includes colour of eyes and hair.
Reaction to sun exposure  The way your skin reacts to sun exposure is another important factor in correctly assessing skin type.
Tanning habits: How often do you tan?

It’s possible to fall in the extreme range of two types: you may have features from both.

Though everyone is at risk for damage as a result of excessive sun exposure, people with skin types I and II are at the highest risk and most susceptible to photoaging. In European and North American adult populations with skin types I, II and III, the prevalence of clinically detectable photoaging may be as high as 90 per cent.

How can I prevent photoaging?
  • Protect skin as best as you can while outside, especially between 11 am and 3 pm when the sun’s UV rays are strongest.
  • Seek shade whenever possible, including from trees, shade coverings, buildings, etc.
  • Wear clothing that covers as much skin as possible, and broad-brimmed (at least five-inch-wide) hats.
  • Sunscreen should be worn daily and not just at times of significant sun exposure.
  • Wear a broad spectrum sunscreen (minimum SPF 30) that protects against UVB and UVA. Reapply after swimming or heavy exertion. Look for the CDA’s logo for effective products that meet these criteria.
  • Apply sunscreen liberally to get its intended effect. Protect especially well the face, ears, neck and hands. These areas are exposed the most, and show sun damage first. Women should include the exposed upper chest. Lips are also very prone to photoaging.
  • Use cosmetics such as moisturizer, foundation, lipstick, hand cream and body lotion that contain SPF 30. These should be used in addition to a broad spectrum sunscreen.
  • Apply an SPF 30 lip balm.
  • Consult Environment Canada’s UV Index daily reports, and take appropriate precautions based on predicted UV levels.
  • Avoid indoor tanning.
How can I minimize visible signs of aging?

Various treatments available for sun-damaged skin include: injections of botulinum toxin, dermal fillers, laser treatment, dermabrasion and chemical peels. Some skin preparations can help restore skin to a more youthful appearance (Vitamin A preparations).

A certified dermatologist can help you decide which treatment regimen will work best for you.