How to choose and apply sunscreen properly

You’re standing in front of a shelf loaded with sunscreen products and don’t know what (or how) to choose one that works for you. Here is an overview to choosing and applying sunscreen to ensure the best skin protection.

SPF stands for Sun Protection Factor. The SPF number on your sunscreen tells you how long it will take the sun’s UVB rays to redden your skin. For example, if you’re using an SPF 30, that means it will take 30 times longer for your skin to become red than if you used no sun protection at all.

When in search of a product, SPF 15 protects your skin against 93 percent of UVB rays, SPF 30 protects against 97 percent and SPF 50 is about 98 percent effective at warding off the sun’s harmful rays. No sunscreen is 100 percent effective.

It’s important to choose a product that protects from both UVB and UVA rays. These are referred to as broad spectrum and are sunscreens that block UVA rays in the same proportions that SPF blocks UVB rays.

How much sunscreen do you need? The American Academy of Dermatology recommends applying generously, using about one ounce of sunscreen (a standard shot glass) for your whole body, then reapplying every two hours.

Which is first, moisturizer or sunscreen? Sunscreen should always be your last step. If you’re applying moisturizer, wait at least 20 to 30 minutes before applying sunscreen so you do not dilute your sun protection, then reapply every two hours (even if you’re not swimming) to ensure proper protection. It’s important to note that even water resistant or very resistant sunscreen is only good for 40 to 80 minutes while swimming since there is no such thing as a waterproof sunscreen.

Even naturally dark skin needs sun protection.