How to Choose Sunscreen | Smart Sun Protection Starts Here

Sun protection comes down to a few straightforward decisions, not a chemistry degree. The right sunscreen blocks both UVA and UVB rays, matches your skin type, and fits into your morning routine without fuss. The “best” sunscreen is simply the one you’ll use every day. Here’s what matters most, starting with the label.

SPF, Broad Spectrum, and Water Resistance: What the Label Tells You

The SPF number measures UVB protection only — the rays that cause sunburn. An SPF of 30 blocks about 97% of UVB rays, which is the minimum you need. For intense outdoor activity or if you burn easily, choose SPF 50+, which blocks about 98%. Higher numbers offer marginal extra protection and may give a false sense of security about reapplication.

UVA rays penetrate deeper and cause premature aging and skin cancer. That’s why “Broad Spectrum” is mandatory — it confirms the product protects against both UVA and UVB. The FDA has also banned the terms “waterproof” and “sunblock” as misleading; look for “water-resistant” followed by the duration (40 or 80 minutes). Reapply after swimming, sweating, or towel-drying.

Mineral vs. Chemical Sunscreen: Which Type Should You Choose?

Mineral (physical) sunscreens use zinc oxide or titanium dioxide to sit on the skin’s surface and reflect UV rays. Chemical sunscreens absorb UV radiation and convert it to heat. Both are safe and effective when used correctly, but your circumstances may make one a better fit.

• Mineral formulas are preferred for sensitive skin, melasma, and children over six months. They work immediately upon application and are less likely to irritate. Tinted mineral versions with iron oxide help prevent pigmentation irregularities on medium and dark skin tones.
• Chemical formulas tend to be lighter and absorb more easily, making them a good choice for oily or acne-prone skin. If your skin is sensitive, avoid oxybenzone (benzophenone) and opt for unscented, hypoallergenic options.

How to Apply Sunscreen Correctly

Application technique matters as much as the product. Apply sunscreen 15 minutes before going outside to allow it to bind to the skin. Use about one ounce (a shot glass full) for your entire body and about a quarter teaspoon (nickel-sized amount) for your face and neck.

Don’t miss common spots: ears, the back of the neck, the tops of your feet, your hairline, and your lips (use an SPF lip balm). Reapply every two hours, or immediately after swimming, sweating heavily, or towel-drying.

Sunscreen alone isn’t enough. Supplement it with UPF-rated clothing, a wide-brimmed hat, and sunglasses. For infants under six months, the FDA advises keeping them out of direct sun entirely; sunscreen is not recommended at that age. For children over six months, mineral sunscreens are the preferred choice.

Common Sunscreen Mistakes to Avoid

Even the best formula fails if you make these errors. Combined sunscreen-and-insect-repellent products sound convenient but should be avoided — sunscreen needs reapplication every two hours, while repellent should not be reapplied that often. Apply them separately. Sunscreen powders also pose inhalation risks, especially for scalp use, and are not recommended.

Do not rely on makeup or powders that contain SPF for your primary protection. Their coverage is typically too thin and uneven to provide real-world protection. A dedicated sunscreen underneath is essential. Finally, discard sunscreen that is past its expiration date or has been opened for more than three years — if the texture or smell has changed, toss it.