What does SPF mean? Facts and Myths About SPF Numbers on Sunscreen Lotions

Child Care

No wants to walk away from a family vacay or a relaxing day at the pool looking and feeling like a red hot lobster. So how do we go about preventing sunburn or even skin cancer? We buy the highest SPF sunscreen at $9.00 a pop. But is the cost of SPF 100 really worth it? What does SPF mean, really?

Many people are ashamed to admit they have no idea. One may think that sunscreen with an SPF of 50 provides stronger protection against sunburn on fairer skin. Or that 30 SPF would provide just enough protection without compromising a well-needed tan.

But think again. Here’s the scoop on how SPF really works and which sunscreens are best to use.

What does the SPF number on sunscreen lotions mean exactly?

A Sun Protection Factor of 15, 30, 45, 100 is not an indicator of strength for specific skin types, but the amount of time the lotion will protect you from (UV) B rays. While it typically takes ten to twenty minutes for skin to burn without sunscreen, with an SPF 30, it would take 30 times as long for you to burn (300 – 600 minutes). SPF 15 blocks about 94% of UV rays, SPF 30 blocks 97% of rays and SPF 45 blocks about 98% of rays. Most doctors agree that going any higher than SPF 45 is a waste of your money.

Why is Sunscreen Important?

Thirty percent of adults and seventy percent of children report at least one sunburn a year. A bad sunburn could potentially land you in an emergency room while frequent exposure to UVA rays can significantly increase your risk of developing skin cancer and wrinkles.

Which SPF Sunscreen Do I Buy?

Coppertone, Banana Boat, or Target? There are so many brands on the market and yes, some brands are better than others. But to start, look for a water-resistant, broad spectrum sunscreen. “Broad spectrum” or “multi spectrum” indicates protection against more than one type of UV radiation. Just remember, apply sunscreen throughout the day especially if you are active. But the best thing to do if you want to catch some outdoor play without the risk of sunburn or heat exhaustion, avoid the most intense sun between 10am and 4pm.

For more information, check out the American Association of Dermatology’s infographic on selecting a sunscreen.

For another look at an important summer health topic, see our article on secondary drowning.

→ Looking for a 24-hour ER in Tyler, TX 75701 or Longview, TX 75605? Visit Hospitality Health Emergency Room for professional care without the long wait times. To prepare in advance for that sunburn before it happens, bookmark our page for urgent care Tyler Texas and beyond can depend on.