Sunscreen Basics: What You Need to Know

Ever wonder why some sunscreens feel greasy while others disappear like magic? It all comes down to the formula, SPF rating, and how you apply it. In this guide we’ll break down the science in plain English, so you can pick a product that actually protects your skin without making you look shiny.

How SPF Works (And Why Bigger Isn’t Always Better)

SPF stands for Sun Protection Factor. An SPF 30 sunscreen blocks about 97% of UVB rays; SPF 50 blocks roughly 98%. The jump from 30 to 50 isn’t a huge leap in protection, but it does give you a bit more breathing room if you’re out for hours. UVA rays, the ones that cause long‑term aging, aren’t measured by SPF alone—look for “broad spectrum” on the label to make sure you get both types covered.

When you first slap on sunscreen, it spreads thinly and only a fraction of the labeled protection is active. That’s why reapplying every two hours (or after swimming) matters more than picking the highest number on the shelf.

Tips for Picking the Best Sunscreen

1. Know Your skin type. If you have oily or acne‑prone skin, go for a gel‑based or “non‑comedogenic” label. Dry skin benefits from creams with added moisturizers like hyaluronic acid.

2. Check the ingredients. Physical blockers (zinc oxide, titanium dioxide) sit on top of your skin and are less likely to cause irritation. Chemical blockers absorb UV light but can sting sensitive eyes.

3. Water resistance matters. If you’re swimming or sweating, choose a product labeled “water‑resistant 80 minutes.” It doesn’t mean it’s waterproof—just that it stays effective longer under moisture.

4. Don’t forget the easy spots. Ears, back of neck, and tops of feet get missed often. A spray or stick can help cover those hard‑to‑reach areas without a mess.

5. Read the expiration date. Sunscreen loses potency after about three years, sometimes sooner if stored in hot places. Keep it in a cool, dark cabinet to extend its life.

Remember, sunscreen is just one piece of sun safety. Wearing hats, sunglasses, and seeking shade during peak hours (10 am‑4 pm) multiplies the protection you get from that little bottle.

Now that you know how SPF works and what to look for, you can shop with confidence. Pick a product that feels good on your skin, reapply regularly, and enjoy the outdoors without worrying about hidden damage.