This summer, as with every summer, there’s an article making the rounds on social media that says that sunscreen causes cancer. That is not true. But, it is true that it isn’t always going to 100% protect you.
One of the great ironies of the world is that our sun can give us cancer. It’s literally the reason why there is life on Earth, and it is what sustains every living thing. And yet, if we spend too much time in it, it can kill us. What’s up with that? I assumed that only people get sunburns, but was a little delighted (and then felt immediately bad about it) to learn that whales and dolphins get sunburnt too. Any animal with exposed skin can get a burn, which could lead to cancer. Lots of animals, like hippos, secrete their own sunscreen. People don’t secrete sunscreen, but we are very clever and have been creating it out of stuff we find for thousands of years.
The sun sends out all kinds of radiation on the electromagnetic spectrum. A small bit of this spectrum is visible light, which is, just as it sounds, light that we can see. Right next to visible light on the spectrum is ultraviolet light, or UV. There are two types of UV that we care about: UVA and UVB. Both are harmful to us by damaging our dna, which can cause cancer. UVA rays are much more common, but much less dangerous. UVB rays penetrate further into the skin and are more responsible for skin cancer, although not 100%.
Sunscreen works in two ways: by deflecting some UV rays and absorbing others. Inorganic compounds, like zinc oxide or titanium dioxide, physically reflect the rays like little mirrors. Organic compounds, like avobenzone or oxybenzone, absorb the rays before they can reach your skin. These organic compounds can only absorb so much, which one reason you should reapply.
The first commercial sunscreen came onto the market in 1940s, but many of the very effective ones didn’t come out until the 1970s. And yet, incidences of melanoma in Americans have more than doubled since the 1980s. Why?
One boring reason is because a lot of our population is getting older. Chances of cancer increase with age, so baby boomers are skewing our statistics.
One not-so-boring reason is the increased popularity of tanning beds. This most greatly affects cancer rates in young women. Don’t go to tanning beds, friends!
Our favorite enemy climate change could also be a potential factor. The ozone layer protects us by scattering some of the sun’s rays, so even though it’s getting better, the result is more skin cancer for humans. The biggest hole in it is around Australia, which might contribute to the reason why there’s more skin cancer down under.
And now we come to maybe the biggest reason of all: because we all trust sunscreen too much. We know that wearing sunscreen protects us, so we feel more confident spending more time in the sun. Unfortunately, that’s only true if we use it correctly, which most of us don’t. Let’s be honest; who actually reapplies every 30-90 minutes like we’re supposed to? According to the World Health Organization, we’re only using less than half as much as we should, and we don’t reapply as often as we should. In addition, in America, the SPF value on a bottle only measures UVB protection, even though we now know that UVA is also harmful.
But do not fear! There are ways to lower your risk of skin cancer, many of which I’m sure you already know:
- When choosing a sunscreen, make sure it’s between 30-50 SPF. Anything higher than 50 SPF doesn’t offer any more protection.
- Also be sure to pick one that says “broad spectrum” or “UVA and UVB protection”.
- Make sure you’re using enough sunscreen, and reapply as often as the bottle says.
- Wear hats, sunglasses, and other skin coverings when possible.
- Limit your sun exposure in general, especially between the hours of 10 am And 4 pm.
- Side note: don’t ignore these suggestions if you have darker skin. While the melanin in your skin will protect you somewhat, it’s not a guarantee that you won’t get skin cancer.
- If you live somewhere with higher elevation, like Salt Lake City, you have to be more careful because there’s less atmosphere between you and the sun.