Dermatologist Shereene Idriss breaks down why a viral claim about sunscreen causing cancer is wrong. The study of 470,000 people confuses correlation with causation: people who use sunscreen tend to have fair skin and spend more time in the sun, so higher cancer rates reflect UV exposure, not the sunscreen. Randomized trials show sunscreen actually lowers skin cancer risk.
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UV radiation, like hot dogs, can kill you. Have I been lied to as a Florida man about sunscreen protecting me from cancer?
Yes, it appears we've all been lied to. Unfortunately, this massive study of over 470,000 people confirms it.
Anybody ever tells you that a study has shown that sunscreen causes skin cancer, please do not stop watching so you could see where they're making their mistakes. An observation is an observation. You could realize that two two things are happening at the same time. We sell more ice cream in the summertime, and there are more shark attacks in the summertime. It doesn't mean that because we sell more ice cream, there are more shark attacks. So saying that people who wear sunscreen have more skin cancer, you're missing the almighty third factor: the sun. People who tend to wear more sunscreen are people who are higher risk. Either they get burnt very easily, they're very fair, or they spend a lot of time outdoors. And so being naturally higher risk, or putting yourself in a situation that makes you higher risk, is going to be correlated with an outcome. The second thing that he does in this video, which a lot of people do when they're trying to prove their almighty force, is he says something wrong and strong.
Sunscreen all the time, you're blocking your body's ability to synthesize vitamin D, which is critical for cancer defense.
Just take a quick step back. Sunscreen use is not going to block your vitamin D production because of one very simple thing: you're human. And because you're human, you're not perfect. Sorry to break it to you, you suck. And you do not have the capacity or the ability to cover every square inch of your body surface area. So UVB is going to still hit your skin and get absorbed by your skin, and you're still going to be able to produce enough vitamin D. The things that we do know for sure is that UV radiation is classified not nationwide but worldwide as a human carcinogen. That means UV radiation, like hot dogs, can kill you. Number 2, sunscreens reduce UV exposure but do not eliminate UV exposure. You're still being exposed to the sun because again, you're not perfect, it's going to hit your skin. And number 3, randomized controlled trials, the gold standard, show that sun exposure is linked to an increased risk of certain skin cancers like squamous cell carcinoma or precancerous lesions. And long-term follow-up has shown a decrease in invasive melanomas. The complete opposite of what this man said, and why dermatologists like yours truly to this day continue to recommend that you, my friend, wear the damn sunscreen.
