The Reason Why Sun Exposure is So Bad For Skin
Repeat after me (out loud, at least three times): There is no such thing as a safe tan.
That billion-years-old gaseous orb of hydrogen and helium blazing millions of miles away at the center of our galaxy does not discriminate by color, creed, gender or religion when blessing all earthlings with life-giving warmth, comfort, vitamin D...and ultraviolet radiation, twofold.
Ok, darker skin tones have a little bit more natural protection thanks to higher doses of pigment-giving melanin, but the damage from sun exposure is still being done and that base tan you’ve convinced yourself is a shield against damage is actually a sign of damage. Your skin, comprising 16% of your body mass, is the only shield you’ve got and when it burns or tans it’s in damage control mode.
If you’ve heard it once, you’ve heard it a thousand times: Sunscreen is non-negotiable, your skin’s saving grace, the only step you should never, ever skip even on cloudy days...but why? What’s really going on underneath your skin’s surface when it comes into contact with the sun’s rays? And aren’t sunscreens killing our coral reefs? Pretty sure the ocean is more important than my skin’s health...amiright?
Before soaking up the sun, let’s soak up a few life lessons on our relationship with sunscreen.
This is What is Happens To Your Skin When You Get a Sunburn
Your skin is trying to shed damaged cells, fast
UV rays penetrate your skin, damaging cells and triggering an inflammatory response from your body in the form of dilated blood vessels to increase blood flow to the affected area. That’s why sunburned skin is red and warm to the touch. At the same time, your skin tightens as it loses moisture and the damaged cells release chemicals as a warning message to our bodies which the brain translates into a painful burning sensation. Then, white blood cells doing their guardian-of-your-personal-galaxy thing attack the damaged cells to remove them. Cue peeling. (1, 2, 3)
This Is What Happens To Your Skin When You Tan
A phenomenon some of us experience rapidly, others not at all tbh
So you burned a bit. No big deal, you think. By tomorrow it will be a nice, healthy base tan to get me through the rest of the sunny season unscathed. If only. The color change your skin undergoes when exposed to the sun’s UV rays is because your skin begins to distribute more melanocytes, darker pigment cells, and piles them on top of the at-risk cells’ nucleus, like an umbrella. The more threatened your skin, the more melanin it layers on to form a pigment barrier that, yes, protects your skin...but, at best, equivalent to SPF 3 sunscreen. Yes, 3. Not exactly enough to prevent damage down to the DNA level. (4, 5)
Sun exposure and premature aging
A.k.a. Photoaging and wrinkles (not the smile-lines kind)
We’ve all seen it or experienced it — dark spots that never faded when the tan did, wrinkled skin before its time, a distinctly leathery texture. Although premature aging is caused by many things, science is clear: unprotected UV exposure takes its toll by breaking down the collagen and elastin fibers needed for firm, healthy skin. But appearances aren’t the real reason derms and moms everywhere want us slathering on sunscreen. (6)
Also, Increased Risk of Cancer
On skin, it surfaces two ways: melanoma and non-melanoma
Melanoma is less common, but more dangerous and accounts for the majority of skin cancer deaths each year. Rather alarmingly, and despite the American public’s insistence that is uses enough sunscreen, the rate of melanoma deaths has steadily increased since records were first kept and, according to the National Cancer Institute, have more than tripled since the 1970s. The good news, melanoma is almost always curable when detected earlier. At this point, it’s important to note that predisposition to skin cancer can be hereditary. But there is also strong evidence linking skin cancer to exposure to UV rays, both UVA and UVB. (7, 8, 9)
UVA vs. UVB Rays: Is One Worse Than the Other?
They behave differently, but both or linked to skin cancer
UVA and UVB rays have different wavelengths which allow them to penetrate different layers of the skin. UVA rays, or aging rays, are longer and cause wrinkles and dark spots. Often overlooked is UVA rays ability to pass through glass, which means they’re doing damage even when you're just sitting in traffic. UVB rays on the other hand, or burning rays, are shorter and only penetrate the outermost layer of the skin, causing sunburn. They don’t move through glass, but both UVA rays and UVB rays are cancer-causing. This is why derms always recommend broad spectrum — because it blocks both. (10, 11)
But I Heard Sunscreen is Just as Bad For Me
Well, you’re not exactly wrong
There is some literature that supports the fear that some sunscreens are absorbing through our skin and doing their own kind of damage as hormone disruptors lurking in our blood, breast milk and babies. Perhaps even scarier, some sunscreens are a bummer for our oceans, contributing to coral reef bleaching. So if the choice is 1) wear sunscreen to save myself but harm the planet or 2) don’t wear sunscreen to save the planet and risk my skin’s health or 3) wear sunscreen but never dip my toes in the ocean again...well, what kind of a choice is that? (12)
Not All Sunscreens Are Created Equal
Chemical vs. physical sunscreens pros and cons
Physical (or mineral) sunscreens work like a shield, sitting sit on the surface of your skin and deflecting the sun’s rays. They contain the active ingredients zinc oxide or titanium dioxide, usually in the form of nanoparticles. Even though physical sunscreens tend to rub off more easily, are thicker and more likely to leave a white residue, opt for this sunscreen if you have sensitive skin...they’re less irritating.
Chemical (or organic) sunscreens work like a sponge, absorbing and scattering the sun’s rays. Their formulations spread more easily, stay on better and don’t leave a white residue...which make them a favorite among consumers. However, they also tend to be more pore-clogging and come with an increased risk of irritation due to the cocktail of chemicals required to deflect both UVA and UVB rays. Common active ingredients include oxybenzone, avobenzone, octisalate, octocrylene, homosalate and octinoxate.
Organizations like the Environmental Working Group and the International Coral Reef Institute have pinpointed oxybenzone as potentially problematic. Oxybenzone, arguably the most studied of all the understudied sunscreen ingredients, has been found to cause allergic reactions and increased irritation, especially on sensitive skin, and may be linked to hormone disruption. Yikes!
Moreover, oxybenzone induces coral bleaching, damages coral DNA and is an endocrine disruptor which impacts coral growth. And it’s showing up in our oceans to the tune of some 20,000 tons...a year, from both swimmers and wastewater treatment plans. Although concentrations are variable from case-to-case, it’s an alarming warning considering our already-stressed-the-f***-out coral reef situation. Maybe best to avoid chemical sunscreens with oxybenzone until more research gives us more concrete answers. (13,14)
How Much SPF is Enough SPF?
And a refresher on what even is SPF
The rule of thumb is to apply sunscreen to all exposed skin (including the tops of your feet!) 15 minutes before heading outdoors. Most adults need a shot glass full of sunscreen for allover coverage(Now you have a reason to bring shot glasses to the beach, you’re welcome.) Reapply every two hours. Unless you’re swimming or sweating, then reapply immediately after. That advice doesn’t change, even if you’re using SPF higher than the recommended 30. That’s because SPF is a measure of sun protection factor not the length of time you can spend in the sun. Nor is SPF, say, 30, twice as strong as SPF 15. SPF 15 blocks roughly 94 percent of rays, while SPF 30 blocks 97 percent and SPF 45 blocks upwards of 98 percent. After that, the blockage power increases are minimal to none. (15)
I’m Vitamin D Deficient, So I Actually Need More Sun, Thanks!
Get it from a combination of food, supplements and, yes, a few minutes of unprotected sun
Like, five minutes max outside without sunscreen...but try to avoid the 10 am to 2 pm hours when the sun is at its strongest. Fun fact: the recommended vitamin D intake is between 1,000 and 2,000 IU’s a day. To put that in perspective, a glass of milk has around 100 IUs. You’d have to drink a ton of milk every day to absorb adequate levels of vitamin D, but 10 minutes in the sun without sunscreen could get you as much as 5,000 IUs. So, yeah, a little bit of sun is healthy but you don’t need to “lay out” for hours to get your vitamin D fix...unless you’re in Seattle in which case just stick to supplements and good luck ever getting a tan. (16)