00:00There's a sunscreen on the drugstore shelf right now that costs about $8, protects your skin exactly
00:05as well as the $40 bottle sitting next to it, and almost everybody walks right past it.
00:09Stick with me, because before this is over, I'll show you the single number on the label that
00:13actually matters, why nearly every homemade sunscreen recipe online is quietly putting
00:18people in the hospital, and the cheapest, most reliable sun protection on the planet,
00:23which is very likely hanging in your closet right now. But first, you have to understand
00:28how the sun actually wrecks your skin, because the man who finally worked out how to measure
00:31protection only did it after a mountain nearly roasted his face off. I went looking for a simple
00:37answer and fell into a genuinely strange story. Here's the whole thing. Start with the damage,
00:43because it makes everything after it makes sense. Sunlight carries ultraviolet radiation,
00:47and it comes in two flavors that matter. UVB is the shorter wave. It hits the surface,
00:53and it's the one that burns you, the one that turns you red and peeling after an
00:57afternoon you'll regret. UVA is the longer wave. It slips deeper into the skin, and it's the one
01:02that quietly ages you, breaking down the collagen that keeps your face from looking like a leather
01:07wallet at 50. Both of them do the same ugly thing at the bottom of it. They slam into the
01:12DNA inside
01:13your skin cells and physically break it. Your body repairs most of that every single day. But every so
01:18often, a repair goes wrong. This broken cell keeps copying itself. And that's the road to skin cancer.
01:24So this isn't a vanity issue. It's the most common cancer there is. And it comes down to how much
01:29unprotected ultraviolet your skin soaks up over a lifetime. Now, SPF. Hold this idea because it's
01:36the thing the entire homemade sunscreen disaster crashes into. SPF is not an ingredient, and it's not
01:41a vibe. It's a measured number, taken in a lab, on real skin under controlled ultraviolet lamps.
01:47They apply a precise, thick layer, blast it with UV, and measure how much longer the skin takes to redden
01:53compared to bare skin. That ratio is the SPF. SPF 30 blocks about 97% of UVB. SPF 50 about
02:0298.
02:02And the quiet catch is that the number only holds at the lab dose, which is far more than any
02:07normal
02:07human actually slathers on. So SPF is a figure you can only get by measuring. You cannot eyeball it.
02:13You cannot blend it in a bowl and hope. And that one fact is where thousands of years of human
02:18cleverness drive straight off a cliff. Because people have been fighting the sun for a very
02:23long time, and the history is a parade of confident nonsense. Go back to ancient Egypt,
02:27and you'll find them grinding up rice bran, jasmine, and lupine and rubbing it on their skin.
02:32Give the Egyptians some credit, actually. A few of those plant extracts genuinely absorb a sliver of
02:37ultraviolet, so they were accidentally onto something, the way a stopped clock is onto something.
02:42The ancient Greeks went the other way and oiled themselves down with olive oil before the games,
02:46which does roughly nothing for UV, and mostly just made them shiny. And in Myanmar, people have worn
02:52a pale bark paste called thanaka on their faces for over 2,000 years. You still see it today. And
02:58it
02:58turns out to offer a little real sun protection, which is more than the Greeks can say. Then comes
03:03my favorite chapter, because two of the things that actually work were discovered by accident,
03:07by men having genuinely awful days. The first is an Austrian named Franz Greiter. In 1938,
03:13he climbed a mountain in the Alps called Pete's Booin, and somewhere up on the glacier, the thin air and
03:18the snow glare cooked his face into a blistering burn. Most people would complain and move on.
03:24Greiter went home, stewed on it for years, and eventually formulated a cream he called Glacier Cream,
03:28and then he did the thing nobody had done before. He came up with a way to actually rate it,
03:33a measured protection factor. That idea became SPF, the number on every bottle you've ever bought.
03:39The sunscreen brand Piz Booin, still on shelves today, is named after the exact mountain that
03:44burned him. A grudge, basically, turned into an entire industry. The second accident was a war.
03:50During the Second World War, an American airman and pharmacist named Benjamin Green watched soldiers
03:55in the Pacific get savaged by the sun, so he cooked up a thick red goo called Red Veterinary Petrolatum,
04:01a sticky, unpleasant barrier that physically blocked the light. It worked, even if it felt like wearing jam.
04:08After the war, he kept tinkering, softened it, blended it with cocoa butter and coconut oil to
04:13make it bearable, and that became Coppertone. The stuff that built the entire suntan aisle started
04:18as wartime field gear. Right alongside it came the lifeguards with the bright white zinc smeared
04:23across their noses. Pure zinc oxide, a physical wall that just bounces the sun off. It looked ridiculous.
04:30It also worked better than almost anything else on the beach. So we cracked it in the 20th century.
04:35Measured protection, real chemistry, regulated numbers. Which makes it almost funny that in
04:41the last decade, the internet decided to throw all of that away and go back to mixing oils in a
04:45bowl.
04:46Here's why the homemade recipes don't just fail. They actively put people in danger.
04:51The most popular one is coconut oil, passed around as a natural sunscreen. Coconut oil has an SPF of
04:58maybe 4 to 7 on a good day, unevenly. That's not protection. That's an umbrella made of tissue paper.
05:04Then there's raspberry seed oil, which one corner of the internet swears is SPF 30 to 50. A claim that
05:10traces back to a single source and was never properly tested on skin. Carrot seed oil gets the
05:15same treatment. None of it is measured. None of it is stable. And all of it hands people the confidence
05:20to lie in the sun for hours believing they're covered. They're not. They burn. And the burn is worse
05:26because they trusted it. The really dangerous version is the one that sounds the smartest.
05:31People say, fine, I'll just stir zinc oxide powder into my lotion. And zinc oxide is a real genuine UV
05:37blocker. That part's true. The problem is that making it work means dispersing it perfectly evenly
05:43across your skin. And that takes industrial mixing you cannot do with a spoon. At home you get clumps and
05:49gaps. Invisible bald spots where the sun walks right through on skin you're sure is protected.
05:54And that's before we get to the loose nano powder you really don't want to be inhaling while you stir.
06:00A real ingredient ruined by the kitchen. So forget the bowl. Here's what actually works. Cheaply, starting
06:06today. The best sunscreen on earth is cloth. A regular t-shirt blocks ultraviolet better than almost
06:12any cream you'll forget to reapply and a dark tight woven shirt does better still. One catch worth
06:18knowing. A wet white shirt loses a big chunk of its protection. So a soaked t-shirt at the beach
06:23is
06:23doing less than you think. But a dry long sleeve shirt and a wide brim hat will out protect a
06:28panicked
06:29handful of lotion every day of the week. They never wash off. And you never reapply them. There's even
06:34clothing rated with a UPF number if you want to get fancy. But you don't need to buy a thing.
06:39The cheapest sun
06:40protection you own is already hanging in your closet. Add shade and a little timing, since the
06:44sun is at its meanest, roughly between 10 in the morning and 4 in the afternoon. And you've already
06:49beaten most people on the beach. When you do buy the bottle, here's the part that saves you real money.
06:55SPF is regulated. An $8 drugstore sunscreen and a $40 designer one, both marked broad spectrum SPF 30,
07:02give you the same protection. You're paying 32 extra dollars for nicer packaging and a smell.
07:07Well, buy the cheap one. And because it's cheap, you'll actually use enough of it which matters
07:11more than the number on the front. That's the thing almost nobody does. People use a fraction
07:16of what the lab used. So they get a fraction of the SPF they paid for. The rule of thumb
07:21is about a
07:21shot glass for your whole body and two fingers worth for your face and neck. Use that much and reapply
07:27every two hours. An SPF 30, you reapply properly, beats an SPF 100, you put on once at 9 in
07:34the morning
07:34and forget by noon. Reapplication is the whole game and the only label reading you'll ever need.
07:39The words broad spectrum, the number 30 or higher, done. Broad spectrum means it covers the aging UVA too,
07:46not just the burning UVB. Everything else on that bottle, sport, sensitive, luxury, infused with,
07:54anything, is marketing. Broad spectrum 30+, used generously, reapplied. You now know more than the
08:00person spending five times as much next to you. So the whole story folds back on itself. For thousands
08:06of years, people rubbed oils and pastes on their skin, chasing a protection that mostly wasn't.
08:11There, the internet revived the exact same mistake with prettier branding. And the real answers turned
08:16out to be a measured number on a cheap bottle and a shirt that's been in your closet the entire
08:20time.
08:21The olive oil was never going to save the Greeks. An $8 bottle and a bit of shade will absolutely
08:26save you.
08:26If this one taught you something, send it to whoever's about to mix coconut oil in a bowl. See you
08:32in the next one.
