Sunscreen Ranker journal
The sunscreen
journal.
Daily, evidence-led notes on SPF, UV filters, and sun protection — every claim sourced, no cap.
- Application Where Sunscreen Goes in Your Routine: Last Skincare Step, Before Makeup Serum, moisturizer, or sunscreen first? Dermatologists settle the order: sunscreen is the last skincare step in the morning, right before makeup. Read it →
- UV science How Much Sunscreen Are You Actually Supposed to Use? The Teaspoon & Shot-Glass Rule Your 'SPF 50' may be performing like SPF 20-25 for one simple reason: most people apply only a fraction of the amount the label was tested with. Read it →
- Seasonal Where to Check the UV Index: Free Government Forecasts and the EPA SunWise App Turn vague sun awareness into a daily habit with authoritative, ad-free UV forecasts you can pull up by ZIP code or right from the EPA's SunWise app. Read it →
- Trends Do You Really Have to Reapply Sunscreen Every 2 Hours? The Rule, Explained The every-two-hours rule isn't arbitrary—filters degrade and rub off—but context like swimming and sweat changes when you actually need to top up. Read it →
- Application Why Dermatologists Say Skip DIY Sunscreen: The SPF 1-6 Problem The viral 'natural homemade sunscreen' trend collapses under testing—most recipes land between SPF 1.5 and SPF 6, and some have no UV protection at all. Read it →
- UV science When Is UV the Strongest? The 10 a.m.-4 p.m. Rule Explained There's a simple, memorable window for the most intense sun of the day—and understanding solar noon explains exactly why it exists. Read it →
- Trends RFK Jr. vs. Sunscreen: How the MAHA Movement Made SPF a 2025 Flashpoint When a federal health official questions sunscreen, the noise gets personal—here's how to separate 2025's culture-war framing from the cancer-prevention evidence. Read it →
- Seasonal How Long Until You Burn? Reading Burn Time From the UV Index and Your Skin Type Instead of guessing when you'll burn, learn the simple inverse rule that links the UV Index and your Fitzpatrick skin type to your personal safe-sun window. Read it →
- Trends SPF 30 vs 50 vs 100: Does a Higher Number Really Protect You More? The real percentages behind SPF 30, 50 and 100 are closer than the marketing suggests—and a big number can quietly encourage riskier behavior. Read it →
- Application The Spots Everyone Misses: Ears, Eyelids, Lips, Scalp and Feet The places you forget to protect are often the ones at highest cancer risk—here's a body-map checklist for the ears, eyelids, lips, scalp and feet. Read it →
- UV science Why UV Is Stronger at the Beach, on Snow, and at Altitude Ski trips and beach days hit you with UV from below as well as above—here's the physics of reflection and thin air that makes them so deceptively intense. Read it →
- Application After the Tests Came the Lawsuits: 2025's Wave of US SPF False-Advertising Class Actions The 2025 SPF testing scandals have moved into US courtrooms—here's what the false-advertising class actions allege and what shoppers should take from them. Read it →
- Global The UK Lab Behind the Sunscreen Scandal: TGA's 2025 Warning on Princeton Consumer Research Behind every '50+' on a bottle is a testing lab you've never heard of—and in October 2025 Australia's regulator cast serious doubt on one of them. Read it →
- Sensitive skin Best Sunscreen Texture for Oily & Acne-Prone Skin: Gels, Fluids and Sticks Compared Stop abandoning greasy lotions—matching the right sunscreen format to oily, acne-prone skin is the difference between a product you wear and one you skip. Read it →
- UV science Climate Change Is Now a Skin Cancer Driver: Longer UV Seasons, Slow Ozone Recovery A 2025 review shows warming isn't just longer beach days—it lengthens UV seasons and pushes melanoma rates higher in places that were never sun-prepared. Read it →
- Seasonal High-UV Destinations Where the Index Hits 11+ Year-Round Some destinations sit in the UV Index's 'Extreme' zone every single day — pack for them like you would for the surface of a much harsher sun. Read it →
- Trends What PA++++ and PPD Actually Mean on Asian Sunscreen Labels Those plus signs on your K-beauty sunscreen aren't marketing fluff — PA++++ is a real UVA rating, and here's the number behind it. Read it →
- Application Apply Sunscreen 15 Minutes Before You Go Out — Here's Why Slathering on sunscreen once you're already at the beach leaves a 15-minute window where you're basically unprotected — here's why timing matters. Read it →
- UV science Can You Get Sun Damage Through Car and Office Windows? Your windshield blocks most UVA, but the side window barely tries — which is why drivers age unevenly and why glass isn't real sun protection. Read it →
- Sensitive skin Acne Actives and SPF: The Right Order for BP, Retinoids and Sunscreen Does sunscreen go before or after your benzoyl peroxide and retinoid? Here's the simple, dermatologist-backed sequence that ends the confusion. Read it →
- Seasonal Why the Sun Is Brutal at the Equator: Latitude, Ozone and UV The same midday sun that's mild at home can scorch you on a tropical trip — and the reason comes down to latitude, atmosphere and ozone. Read it →
- Trends Is the SPF in Your Makeup Enough? Why Foundation Falls Short Your SPF 30 foundation sounds like full coverage, but you'd need to trowel it on to hit that number — here's why a real sunscreen layer underneath is non-negotiable. Read it →
- Application Does Daily Sunscreen Cause Vitamin D Deficiency? The Evidence The fear that sunscreen will tank your vitamin D is one of the top reasons people skip it — here's what the clinical research actually shows. Read it →
- Skin cancer Actinic Keratosis: The Skin Precancer You Shouldn't Ignore That rough, scaly patch from years of sun isn't just dry skin — it's a fixable precancer, and treating it early can stop a squamous cell carcinoma before it starts. Read it →