You’ve heard it again and again: Wear sunscreen when you go outside, year-round, no matter the weather. (We’ve even shared our own ClassPass reminders and suggestions to encourage sunscreen use.)
But, like us and probably almost everyone we know, you probably don’t grease up every time you go out. It’s easy to come up with excuses: It’s cloudy, I won’t be out that long, it takes so long to do it, it’ll get all over my dress/expensive workout top/ bathing suit, I’ll just sweat it off anyway…
Yet even a tiny bit of sun exposure can do damage to your cells. You may not notice it now, but the damage is cumulative over a lifetime. We only get one skin, so in the name of protecting it for the long haul, here’s the hot, sweaty truth about what really happens when you soak up the rays.
Ultraviolet A and B
The rays of light emitted by the sun—called UVs and distinguished by their placement on the light spectrum—are invisible but dangerous.
UVB rays are short waves of energy that are quickly absorbed by the outermost layer of skin. The skin, sensing something is wrong, produces inflammatory compounds to protect the cells in the same way other bodily tissues respond to pain, injury or stress. These chemicals irritate the tiny blood vessels found throughout the skin, which swell and produce the telltale redness of sunburn.
While they initially cause a tinge of red to the skin, UVB rays also affect the genetic material in the skin’s cells, increasing the likelihood of cancer and impairing the cells’ ability to repair damage in the future. The freckling and changes in moles that are also common with certain skin cancers, like melanoma, are also associated with UVB rays. The skin’s pigment cells become damaged by their own efforts to filter out the sun as their excessive production of melanin interferes with their DNA.
UVA rays also play a role in the development of skin cancer, and in the shorter term are responsible for premature skin aging due to sun exposure. Because UVA rays are longer, they penetrate more deeply into the skin and damage cell membranes, changing the skin’s elasticity by breaking down collagen and elastin. Wrinkles and sagging, anyone? Again, as the body tries to fight the imbalance with inflammation, blood vessels dilate and with the lack of support, remain permanently dilated (read: spider veins).
Even a moderate tan is an injury to the skin
To dermatologists, tanned skin is damaged skin. The change in color indicates a permanent change to the genetic structures that dictate the future of our skin’s health. As cells replicate and regenerate, they continue to produce copies with the genetic changes. Skin that is further damaged becomes less and less likely to maintain health over a lifetime.
This is why sunscreen is kind of a big deal
These rays are what sunscreen is designed to protect against, by creating a barrier for your tissue to prevent it from absorbing the rays in the first place.
Sunscreen contains compounds that filter sunlight. Like a screen door, some light penetrates, but a good deal is prevented from getting through. Sunblock, which usually contains zinc or titanium dioxide, reflects or scatters rays before they even reach the skin. Many sunscreens include elements of sunblock in their formula.
You probably know how quickly you burn on a sunny day. The sun protection factor or SPF of your lotion will protect you for your typical burn time multiplied by the number on the bottle. For example, a fair-skinned person who normally burns in 10 minutes would be protected for about 150 minutes with a sunscreen with SPF 15.
You’re going to wear sunscreen—here’s how to the most of out of it
If you’re taking the time to apply sunscreen, you might as well get as much protection as you can. Apply liberally at least a half hour before going outside.
Cover up as much as you can, and aim to stay out of the direct sunlight between 10 a.m. and 4 p.m., especially if you live at a higher altitude.
If you’re on antibiotics, birth control pills or other hormonal medications, your skin may be more sensitive to the sun. Check with your primary care provider to see if you should up your sunscreen game further, either by finding a higher SPF or skipping the trips to the beach until your course of meds is finished.
We’re not trying to nag you (well, sort of)
We just like you and want you to have all the information to make the best decision for your skin. Knowing the why and the how can help make sense of an annoying, time-consuming habit, and if you have a good motivator (no sagging! no skin cancer! no spider veins!), you may be more likely to slather on the ‘screen before you head outdoors. We promise, it’s worth it.