No More Hustleporn: If you heard the latest @theallinpod and the sunscreen safety topic @friedberg raised surprised you, let me add some details as a dermatologist.
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@usamasyedMD:
If you heard the latest @theallinpod and the sunscreen safety topic @friedberg raised surprised you, let me add some details as a dermatologist.
I'll explain the 2 types of sunscreen, their safety profiles, and also answer @chamath's Q ("do brown guys need sunscreen?") 👇🏼1/
@usamasyedMD:
There are 2 main classes of sunscreen - physical & chemical. Physical are made up of the organic blockers zinc and titanium which stay on the surface of your skin (don't absorb) and block UV rays. They're VERY safe (no skin irritation). But also thick, and you look like this...
@usamasyedMD:
Chemical sunscreens primarily have ingredients like oxybenzone and avobenzone in the US. These absorb the sun's rays and convert them into heat on the skin surface. They feel lighter and blend easier, but can irritate the skin and ABSORB INTO THE BLOODSTREAM. Because of this...
@usamasyedMD:
...there are huge controversies regarding chemical sunscreen use. Oxybenzone has been implicated as an 'endocrine disruptor' meaning it can affect various glands in the human body and disrupt hormone levels. There is debate about how substantial this affect is...
@usamasyedMD:
...but the fact that there's any debate at all means a lot of people (including @friedberg, and myself too as you can see from back in Jan) avoid using chemical sunscreens. I especially avoid using them on my child, and think you should too. There's too much we don't know.
@usamasyedMD:
SO.. SUNSCREEN ALL JUST SUCKS?
Physical ones feel thick, chemical ones in the US are unsafe... so now what? Well it doesn't HAVE to be this way. Countries in Europe and e.g. South Korea have NEW chemical sunscreen ingredients like Tinosorb S and Uvinul A Plus which are great!
@usamasyedMD:
They absorb way less than oxybenzone and are far safer, so people in those countries get easy-blending, SAFE sunscreens. In the US, the FDA regulates sunscreens as a drug, so no new sunscreen ingredients have been approved since the 1990s!! This is what @chamath looked like then.
@usamasyedMD:
WHAT SHOULD WE DO IN THE US?
Find a physical sunscreen product of at least SPF 30+ that you dislike least, and make a habit of applying it. Every little helps, even if you don't cake it on. For those with skin of color, TINTED sunscreens are a game-changer for blending.
@usamasyedMD:
So last question: "Do brown people need to wear sunscreen?" The rates of skin cancer in brown people is way less than white people, but lifetime estimates still put it at around 1 in 7 or 1 in 10 depending on the stats you look at. Sun protection minimizes this risk...
@usamasyedMD:
...but it also dramatically delays 'photo-aging'. So even if you're not as worried about skin cancer as a brown guy, wearing sunscreen regularly will keep your skin looking baby smooth over time.
@usamasyedMD:
That's it for this thread - if you have any questions about sunscreen, drop them in the comments below! And if you want more evidence-based skincare content, follow along! 🧪🥼