Sunscreen Ranker journal
The sunscreen
journal.
Daily, evidence-led notes on SPF, UV filters, and sun protection — every claim sourced, no cap.
- Application Reading the UV Index: The Exact Number That Means 'Put Sunscreen On' That little UV number in your weather app has a clear threshold - here's the reading where protection stops being optional. Read it →
- UV science The Hidden Harm of UV: How Sunlight Quietly Disarms Your Immune System Beyond burns and wrinkles, UV does something most people never hear about - it temporarily switches off part of your skin's defenses. Read it →
- Seasonal The UV Index You Can't See: Why Tanning Beds Beat the Midday Sun There's no weather-app number for the bed at the salon - and that's exactly why indoor tanning is so dangerous. Read it →
- Application How to Reapply Sunscreen Over Makeup Without Wrecking Your Look The midday reapplication problem is why most people skip it, here's how to top up protection without ruining your makeup. Read it →
- UV science How UV Light Ages Your Skin: The Science of Photoaging Daily sunscreen is the most evidence-based anti-aging step there is, and the science of photoaging explains exactly why. Read it →
- Reef-safe 2025's Antarctic Ozone Hole Was 5th Smallest Since 1992, But Recovery Is Decades Off The healing ozone layer is a genuine success story, but recovery is decades away and surface UV is still intense, here's why sunscreen still matters. Read it →
- Seasonal UV Radiation and Skin Cancer: The Most Common Cancer in America Skin cancer is the most common cancer in the US, and the single biggest driver is something you can largely control. Read it →
- Application Sunscreen Pills Don't Replace the Bottle: What the FDA Warnings Say 'Drink your sunscreen' supplements sound convenient, but the FDA has been clear that no pill protects your skin from UV. Read it →
- UV science Does Blue Light Damage Skin? What the HEV Research Actually Shows Cutting through the 'blue light skincare' hype: here's what's actually evidenced about visible light and skin, and for whom it matters most. Read it →
- Seasonal Snow Blindness Is Real: What Winter Photokeratitis Does and How to Prevent It Reflected UV off snow can give your eyes a painful sunburn, and it's the best argument there is for goggles on the slopes. Read it →
- Application What 'Broad Spectrum' Really Means, and Why SPF Alone Won't Save You From UVA There's one word on the label that decides whether you're protected from the UVA rays that age skin and drive cancer. Read it →
- Formulation Does Sunscreen Cause Vitamin D Deficiency? A 2025 Trial Adds Nuance to the Myth The 'sunscreen blocks vitamin D' claim is half-wrong and half-right, and a 2025 randomized trial shows exactly where the truth sits. Read it →
- Skin cancer The Sun-D Trial: Does Daily SPF 50+ Really Raise Your Vitamin D Risk? The first large randomized trial to test the sunscreen-vitamin D claim is in, and the real-world answer is more nuanced than the headlines. Read it →
- Formulation Mineral Sunscreens Recalled for 'Splitting': The 2025 Australian Separation Recalls Several zinc sunscreens were pulled in Australia in late 2025 for physically separating in the bottle, here's why that compromises protection. Read it →
- UV science 30 Years of Data: Rising UV Is Driving Melanoma Most in Wealthy, Low-UV Countries A 2025 analysis of 176 countries reframes who is most at risk as surface UV climbs, and it isn't only the sunniest places. Read it →
- Skin cancer AI in the Exam Room: 2025 Studies Show DermaSensor Helps Doctors Catch More Melanomas New 2025 data shows an FDA-cleared AI device helps primary-care doctors miss fewer melanomas, but it doesn't replace your dermatologist. Read it →
- Filter chemistry The SAFE Sunscreen Act Just Became Law: Here's the Real Timeline for Better US Sunscreen A quiet November 2025 law could reshape the US sunscreen aisle, but the better filters won't appear overnight. Read it →
- Filter chemistry The 2025 SAFE Sunscreen Act Targets the Korean and Japanese Filters You Can't Buy in the US A law signed in November 2025 finally pushes the FDA to look at the advanced UV filters that Korea and Japan have used safely for years. Read it →
- UV science How the Ozone Layer Is Your First Line of UV Defense Before any sunscreen touches your skin, a thin band of atmospheric ozone is already filtering the sun's most dangerous rays. Read it →
- Seasonal UV and Your Eyes: Photokeratitis, Cataracts and Why Sunglasses Aren't Optional Sun protection isn't just skin-deep; your eyes are vulnerable to UV too, and the long-term toll can include cataracts. Read it →
- Application Snow Days Are Sun Days: 80% UV Reflection and the Altitude Effect Cold weather doesn't switch off the sun; snow doubles the UV hitting your skin and altitude turns it up further. Read it →
- UV science PA+ to PA++++ and PPD: How Asian Sunscreens Rate UVA Protection Those plus signs on your K-beauty and J-beauty sunscreen are a precise UVA grade, and here's exactly what they measure. Read it →
- Seasonal Can You Get Sunburned Through a Window? The UVA Glass Lets In Glass blocks UVB, so you won't burn at your desk, but the UVA streaming through still ages skin and raises cancer risk. Read it →
- Trends How to Read the UV Index Like a Pro (And Why Tanfluencers Misuse It) The UV Index is a free, location-specific warning system, not a tanning leaderboard, and reading it right keeps you off the burn line. Read it →