Just Say No to Melanoma

Gabrielle Birchak/ June 30, 2025/ Ancient History, Archive, Late Modern History, Modern History, Post Classical

Wel­come back to Flash­card Fri­day here on Math, Sci­ence, His­to­ry! I’m your host, Gabrielle, and today’s episode is all about some­thing small that packs a big punch against one of the most com­mon can­cers in the world: sunblock.

We’ll explore its fas­ci­nat­ing his­to­ry, the sci­ence of how it works, the sta­tis­tics on skin can­cer and melanoma, and why pro­tect­ing your skin is one of the smartest health moves you can make.

A BRIEF HISTORY OF SUNBLOCK

Humans have been bat­tling the sun for thou­sands of years. While the sun gives us life, warmth, and vit­a­min D, it also sends out invis­i­ble ultra­vi­o­let radi­a­tion, UV rays, that can dam­age our skin.

Ancient cul­tures had their own cre­ative solutions:

• In ancient Egypt, peo­ple used rice bran extracts and jas­mine, which mod­ern sci­ence has shown can help absorb UV light.
• The Greeks used olive oil.
• Indige­nous Aus­tralians applied clay and mud, which act­ed like a nat­ur­al barrier.

But the first mod­ern sun­blocks didn’t appear until the twen­ti­eth cen­tu­ry. Here’s how it unfolded:

• 1938: Aus­tri­an chemist Franz Gre­it­er got bad­ly sun­burned while climb­ing Mount Piz Buin in the Alps. Deter­mined to solve the prob­lem, he cre­at­ed one of the first effec­tive sun­screens, which even­tu­al­ly became the well-known Piz Buin brand.
• 1944: In the U.S., Ben­jamin Green, an air­man and phar­ma­cist, devel­oped “Red Vet Pet”, short for red vet­eri­nary petro­la­tum, to pro­tect sol­diers in World War II. This sticky red sub­stance laid the foun­da­tion for the Cop­per­tone brand.
• 1960s–1970s: Sun­screens improved dra­mat­i­cal­ly. Com­pa­nies began devel­op­ing creams with mea­sur­able SPF, or Sun Pro­tec­tion Factor.
• 1980s–1990s: The indus­try saw a huge leap for­ward with the devel­op­ment of broad-spec­trum sun­screens that pro­tect against both UVA and UVB rays.

Today, sun­block comes in lotions, sprays, sticks, gels, and even pow­ders, reflect­ing decades of research into skin health and photoprotection.

THE SCIENCE OF HOW SUNBLOCK WORKS

So, how does this stuff actu­al­ly work?

Sun­block and sun­screen fall into two main categories:

1. Phys­i­cal (min­er­al) block­ers ,  like zinc oxide and tita­ni­um diox­ide. These sit on top of the skin and reflect UV rays away, act­ing like tiny mirrors.
2. Chem­i­cal sun­screens ,  with ingre­di­ents like avoben­zone and octi­nox­ate. These absorb UV radi­a­tion and con­vert it into harm­less heat.

The Sun Pro­tec­tion Fac­tor (SPF) mea­sures how well a sun­screen pro­tects against UVB rays, which cause sun­burn. For exam­ple, SPF 30 blocks about 97% of UVB rays, while SPF 50 blocks about 98%. But no sun­screen blocks 100%, so reap­ply­ing and com­bin­ing it with pro­tec­tive cloth­ing is key.

Broad-spec­trum sun­screens pro­tect against both UVB and UVA rays. UVA rays pen­e­trate deep­er into the skin and are strong­ly linked to aging and skin cancer.

MELANOMA AND THE DANGERS OF SUN EXPOSURE

Now, here’s where things get serious.

Melanoma is the dead­liest form of skin can­cer. While it accounts for only about 1% of skin can­cers, it caus­es the vast major­i­ty of skin can­cer deaths.

Let’s look at some statistics:

• Accord­ing to the Amer­i­can Can­cer Soci­ety, in 2025, about 100,640 new melanomas will be diag­nosed in the U.S.
• Around 8,290 peo­ple will die from melanoma this year.
• One per­son dies of melanoma every hour in the U.S.

But here’s the good news:

• Ear­ly detec­tion leads to a 99% five-year sur­vival rate for local­ized melanoma.
• Reg­u­lar use of sun­screen reduces the risk of devel­op­ing melanoma by up to 50%.

One land­mark study from Aus­tralia, pub­lished in Jour­nal of Clin­i­cal Oncol­o­gy, fol­lowed over 1,600 peo­ple for 4.5 years. Those who applied sun­screen dai­ly had 50% few­er melanomas com­pared to those who used sun­screen occasionally.

That’s why I say it loud and proud: Just say no to melanoma.

WHY SUNBLOCK MATTERS (EVEN ON CLOUDY DAYS)

There’s a big myth out there: “I only need sun­screen when it’s sun­ny.” Not true!

• Up to 80% of UV rays pass through clouds.
• Snow, sand, and water reflect sun­light, increas­ing exposure.
• Even on cold or over­cast days, you’re still get­ting hit with UV radiation.

And if you’re think­ing, “I’m indoors, I’m safe”, think again. UVA rays can pen­e­trate glass win­dows, mean­ing that dai­ly sun­block use mat­ters even if you’re inside by a win­dow or driving.

HOW TO USE SUNBLOCK EFFECTIVELY

Here’s your crash course in apply­ing sun­screen the right way:

• Use at least a shot glass amount (about 1 ounce) for full body coverage.
• Apply 15–30 min­utes before going outside.
• Reap­ply every two hours or imme­di­ate­ly after swim­ming or sweating.
• Don’t for­get sneaky spots: ears, scalp, tops of feet, lips, and the back of your neck.

And choose:

• SPF 30 or higher.
• Broad-spec­trum.
• Water-resis­tant if you’re swim­ming or sweating.

THE MATH OF PREVENTION

Here’s a lit­tle math twist for my fel­low num­bers fans:

If SPF 30 blocks 97% of UVB rays, and SPF 50 blocks 98%, you might think SPF 100 blocks dou­ble the rays, but it doesn’t. SPF 100 blocks about 99%.

This means:

• SPF 30–50 is usu­al­ly suf­fi­cient for most people.
• No sun­screen is bul­let­proof, you still need shade, hats, and pro­tec­tive clothing.

GLOBAL IMPACT AND THE FUTURE OF SUN PROTECTION

Melanoma rates have been ris­ing for decades, espe­cial­ly among young peo­ple and those with fair skin. But thanks to bet­ter aware­ness and prod­ucts, we’re see­ing improvements.

In Aus­tralia, one of the sun­ni­est places on Earth, skin can­cer rates have start­ed to decline in younger gen­er­a­tions because of strong pub­lic health cam­paigns like “Slip, Slop, Slap”, Slip on a shirt, Slop on sun­screen, Slap on a hat.

In the future, we’re like­ly to see:

• Wear­able UV sensors.
• Cloth­ing with built-in SPF.
• More reef-safe for­mu­las that pro­tect the ocean as well as our skin.

TAKEAWAYS ,  AND JUST SAY NO TO MELANOMA

Here’s what I want you to remember:

1. Sun­screen has a fas­ci­nat­ing his­to­ry, from ancient rice bran to mod­ern sprays.
2. It works by reflect­ing or absorb­ing UV rays and reduc­ing your risk of skin damage.
3. Melanoma is dead­ly but large­ly pre­ventable, and sun­screen cuts your risk by up to 50%.

So please, just say no to melanoma. Pro­tect your skin like your life depends on it, because in many cas­es, it does.

Thank you for join­ing me today on Flash­cards Fri­day at Math! Sci­ence! His­to­ry!  If you enjoyed this episode, be sure to sub­scribe, leave a review, and share it with your friends and fam­i­ly. And the next time you head out­side, remem­ber to slather, smear, spray, and say no to melanoma.

Until next time, carpe diem!