Skin Aging Due to Sun Exposure: All You Need to Know
It's well known that moderate sun exposure is good for our health - it lifts our mood and helps our body produce vitamin D. However, too much time in the sun can damage our skin, both on the surface and on the cellular level.May 17, 2022 7 minutes read
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Summer is finally here. And while we may enjoy all its perks, we need to keep in mind that this is the most challenging season for our skin. Solar radiation has shown to have detrimental effects on the skin's health and appearance, causing premature aging, called photoaging, as well as allergies and even skin cancer. Therefore, while enjoying all the in-the-sun activities, we need to adequately treat and protect our skin, both before and after sun exposure.
So, let's dive deeper into how the sun affects our skin and what we can do to protect it and, ultimately, prevent its premature aging.
How Does Sun Affect Your Skin?
Sunlight or ultraviolet (UV) light is classified into three main types: ultraviolet A or UVA rays, ultraviolet B or UVB rays, and ultraviolet C or UVC rays. All of these rays have different wavelengths, measured in nanometers, and so:
- UVC has a wavelength of 100-279 nanometers and is almost completely absorbed by the Earth's atmosphere and ozone layer;
- UVB has a wavelength of 280-314 nanometers and is only partially absorbed by the ozone layer, meaning that some of the UVB rays always reach the surface of our planet;
- And finally, UVA has a wavelength of about 315-399 nm and, therefore, can't be absorbed by the ozone layer.
Therefore, UVC radiation doesn't pose too much health risk, while both UVB and UVA radiation can affect our skin health. Even though UVA radiation may not feel as strong as UVB, it does penetrate the deeper layers of the skin and is present year-round.
UV light, primarily UVB and UVA, ultimately damages the DNA in the skin cells, impairing their vital functions and the ability to self-regenerate, and causing mutations that can eventually lead to the premature signs of skin aging and, in the worst case, skin cancer.
In fact, research suggests over-exposure to solar radiation is responsible for almost 80% of visible signs of aging, such as dark spots and wrinkles, especially on those parts of the body that are frequently exposed to the sun, including the face, back of the hands, forearms, and neck. It further goes to say that chronological skin aging, which is essentially aging caused by the passage of time, is accelerated by chronic exposure to the environment, especially the UV radiation from the sun, causing:
- Diminished self-renewal capacity of the epidermis, or the outer layer of the skin which provides natural barrier function;
- Altered thermoregulation function of the sweat glands;
- Gradual fragmentation of the collagen framework in the dermis, the deeper layer of the skin, leading to weakened elasticity and resiliency;
- And also affected skin pigmentation, wound healing, immunity, vasculature, and subdermal fat distribution.
All of these factors will sooner or later show on your skin in the form of:
- Yellowish skin color,
- Solar purpura or small purple bruises,
- Solar lentigo (lentigines) or benign lesions on the skin in yellow or brown color,
- Red cheeks,
- Telangiectasia or broken-appearing blood vessels,
- Deep wrinkles,
- Crow's feet or wrinkles in the corners of the eyes,
- Furrows due to gravity and loss of elasticity and firmness of the skin,
- Rough, lux, and leathery skin texture,
- As well as skin that's either excessively dry or oily.
Sun and Different Skin Tones
When exposed to UV light, specific changes are happening inside the skin to protect itself from further damage. Namely, the skin's outermost layer or the epidermis thickens and the melanocytes, skin cells that produce pigment, inside the epidermis start making increased amounts of melanin. This chemical process is called melanogenesis, which is essentially the oxidation of the amino acid called tyrosine.
Melanin is a natural pigment, ranging in color from dark brown to black, which makes our skin look tanned. Its role is to absorb UV light and prevent it from penetrating deeper into the skin and underlying tissues and, to some extent, protect the skin cells from sun damage.
However, it's important to mention that purposefully getting a tan to protect your skin from the damaging UV rays is risky for your health as a tan alone can't provide you with enough protection and can be hazardous.
In addition, not everybody has the same amount of melanin in their skin, and your sensitivity or tolerance to sun exposure will depend on the amount of melanin you have at your disposal and genetic predisposition. Some people, especially those with genetically darker skin tones, are able to produce more significant amounts of melanin in response to UV exposure. In contrast, others, particularly those with fair skin tones, can produce only negligible amounts.
Based on the amount of melanin inside the skin, its reaction to solar radiation, and the ability to tan, we distinguish six different skin phototypes, the so-called Fitzpatrick classification:
- Skin phototype 1 – people with pale-white skin, light-colored blue or green eyes, and naturally blond or red hair: always burn, never tan;
- Skin phototype 2 – people with relatively fair skin tone and blue eyes: usually burn easily and tan minimally;
- Skin phototype 3 – people with darker white or olive skin tones: moderately burn, gradually tan after initial burning;
- Skin phototype 4 – people with light brown skin tones: burn slightly, tan easily;
- Skin phototype 5 – people with brown skin tones; seldom burn, get a dark tan quickly;
- Skin phototype 6 – people with darker brown or black skin tones; never burn, always tan intensely.
In sum, people with fair skin and red hair cannot produce enough melanin pigment and are, therefore, extremely susceptible to both short- and long-term damaging effects of UV radiation. Besides, the melanin inside their epidermis often becomes distributed unevenly, leading to freckles. Similarly, people with albinism often have extremely little or no pigment at all, and those with vitiligo have lighter skin patches with no melanin.
However, even those with a skin phototype 5 or 6 – that certainly have more melanin and, therefore, higher inherent protection against the harmful effects of UV radiation – are still vulnerable to the sun-induced skin damage and the long-term impact of unprotected exposure to sunlight.
How to Protect Your Skin From Photoaging
First and foremost, it's vital to note that sun protection is equally important during winter as it is during summer, especially if you're in the mountains surrounded by snow. At every 300 meters above sea level, the chance that your skin will burn increases by 4%. In addition, snow and ice are good reflectors of UV radiation, reflecting up to 80% of sun rays and increasing their damaging effect.
On the other hand, if you're at the beach during summer and run into the water to avoid sunburn, you're making a huge mistake. Water can't protect you from sun damage as about 95% of its radiation goes through it. In addition, water, just like snow, is an excellent reflector, so there's a higher probability of sun damage if you're in the water and next to it.
Furthermore, there's a common misconception that you have to feel the sun's heat to get a sunburn. Intense sun is often followed by the wind in the summer, especially near seas or rivers, which doesn't prevent burning.
Due to these factors, sun protection is necessary throughout the year, not just in the summer. In fact, it's most needed when you're in the mountains covered with snow or near water.
Sun protection involves avoiding sun exposure during the period when the sun is at its peak, between 10 am and 4 pm. In addition, you should wear protective clothing, such as wide-brimmed hats, sunglasses, and long sleeves and pants – choose lighter and natural materials, especially during summer. Moreover, always keep in mind the following five basic principles of sun protection:
#1: Always Wear Sunscreen
Apply your sunscreen or sunblock to all the areas of your body that are exposed to the sun, especially your face, neck, and the back of your hands, 15 to 20 minutes before going outside. Choose the proper SPF (Sun Protection Factor) – dermatologists recommend the SPF of at least 30, bearing in mind that lighter skin tones will need a higher factor. Also, you should reapply your sunscreen every two hours or at shorter intervals if you're sweating or swimming.
#2: Take Care of Your Skin After Sun Exposure
Remember that no sunscreen can block all the damaging UV rays. Therefore, the sun makes our skin particularly vulnerable, and you need to give it additional nourishment after each sun exposure. Choose skincare products with ingredients that restore moisture and elasticity and promote regeneration, such as panthenol, glycerin, aloe vera, hydrolyzed collagen, and others.
It's crucial to check your skin regularly. Pay special attention to your moles and any new spots or changes. If the moles become larger or thicker, with unclear edges and colors, or even bleed, see a doctor immediately. Every month, self-examining our skin is recommended, especially if you're chronically exposed to sunlight. Still, seeing your dermatologist at least once a year, regardless of your skin phototype or sun exposure frequency, is a must.
#4: Pay Attention to Your Diet
Eating foods rich in antioxidants will help your body defend itself from the harmful effects of UV rays. However, a healthy diet still can't be a substitute for good-quality sunscreen, but can undoubtedly be an excellent addition in the fight against damaging environmental factors. Vitamins like vitamin C, E, and A, minerals, lycopene as well as selenium will provide you with solid protection from the inside out.
Therefore, make sure to have these foods on your table as often as you can: nuts and seeds, tomatoes, sweet potatoes, spinach, leafy greens, berries, kiwis, citrus fruits, and fatty fish. Also, don't forget to keep your body hydrated and drink enough water every day.
#5: Say 'No' to Sunbeds
Many health organizations, including the FDA and the American Academy of Dermatology, recommend completely avoiding any artificial UV sources, such as solariums or tanning beds. In July 2009, it was established by the International Agency for Research on Cancer (IARC) that UV-emitting devices are highly cancerogenic to people. In addition to posing a severe risk of getting skin cancer, including melanoma, tanning devices can also cause allergic reactions, premature aging, eye damage, and immune suppression.
Sunbeds shouldn't be used for preparing your skin for sunbathing, as some people, especially younger generations, would think. In these devices, the UVA rays are much stronger than in natural sunlight, and the health risk factor is, therefore, much higher. If you enjoy a sun-kissed skin look, go for self-tanning oils or lotions, a much safer option.
In sum, chronic exposure to UV radiation damages skin cells and results in the premature aging of the skin, called photoaging. Photoaging differs from chronological aging, and it most commonly causes yellowish complexion, deep wrinkles, large freckle-like spots, and rough skin texture, to mention a few. Although people with fair skin are the most vulnerable to the harmful effects of UV light exposure, nobody's skin is completely safe, especially after chronic, prolonged sun exposure without adequate protection.
The skin is our largest organ that protects us from environmental influences. Therefore, it's crucial to take good care of it, nurture, and protect it. So, always wear your sunscreen and apply it liberally and often, regardless of whether you're on summer vacation or a city walk.
Does sun exposure cause aging?
Yes. Chronic exposure to harmful UV radiation, especially without appropriate sun protection, causes premature skin aging. Dermatologists call this type of skin aging photoaging, sun damage, solar damage, and photodamage. Sun damage usually causes rough skin texture, uneven (red and yellow) complexion, deep wrinkles, and dark spots.
How do you stop sun aging?
The best protection against sun aging is avoiding the sun at its hottest, usually between 10 am and 4 pm, depending on where you live. Also, whenever going outside, wear your sunscreen with an SPF of at least 30, as well as protective clothing (long sleeves, pants, sunglasses, and a wide-brimmed hat).
Does the sun destroy collagen?
Yes, damaging UVA sun rays penetrate into the deeper layers of the skin, causing mutations in the cells' DNA and degrading the collagen in the inner layer of the skin, the dermis. And since the collagen is the skin's structural framework, sun damage results in the loss of the skin's elasticity and bounciness, and it starts sagging prematurely.
Is hyperpigmentation a photoaging?
Photoaging causes changes in skin pigmentation, the so-called lentigines. Lentigines, also known as liver spots, occur as small lesions on the skin that have an irregular shape and are dark in color. The most common areas where these lesions appear are those areas of the body that are most commonly exposed to the sun, like the face and the back of the hands.
Can I reverse sun damage?
Unfortunately, there's no effective way to reverse skin damage caused by sun radiation. Chronic sun exposure causes DNA mutations inside the skin cells, and those can't be reversed. However, there are certain skincare ingredients (such as chemical peels and retinoids) as well as procedures (such as laser treatments, fillers, and cosmetic surgery) that can improve your skin's appearance to some extent.