The ultimate sunscreen guide

Jul 29, 2019


With summer in full swing, it’s time to step outside and enjoy many of the fun activities the sunny season offers. It’s also time to up your game when it comes to ultraviolet (UV) sunlight protection.

Too much unprotected UV exposure can increase your risk of skin cancer — the most common form of cancer, and one whose incidence rate is rising.

To protect yourself, you need to wear sunscreen daily. Take a look at our ultimate sunscreen guide and learn how it can help you guard against harmful UV damage.

Powerful, invisible rays

The sun emits two types of skin-damaging UV rays — ultraviolet A (UVA) and ultraviolet B (UVB). Over time, these harmful rays can lead to:

  • Skin cancer, including potentially deadly melanoma.
  • Premature aging. UV damage can cause early wrinkles, leathery skin and age spots.
  • Eye damage. Overexposure to UV rays can increase the risk of cataracts and certain other eye diseases.

Not all UV rays are created equally, however. UVB rays are the main cause of sunburn, and UVA rays are the main cause of aging skin. But both UVA and UVB rays can cause skin cancer. So you’ll want to protect your skin against both types of rays—more on that in a moment!

Understanding your sunscreen

This brings us to sunscreen—an essential tool for avoiding UV damage. When buying a sunscreen, make sure the label says it offers broad-spectrum protection. Broad-spectrum sunscreen guards against both UVA and UVB rays. This means it helps prevent sunburn, skin cancer and skin aging.

When shopping for sunscreen, you’ve likely noticed the SPF ratings. SPF stands for “sunburn protection factor.” The FDA uses SPF ratings to tell you how well a sunscreen protects you from sunburn (those UVB rays). Here’s an example of their difference in effectiveness:

  • SPF 15 protects against 93 percent of UVB rays
  • SPF 30 protects against 97 percent of UVB rays

But you also might have found that some products have different ingredients. According to the American Academy of Dermatology, these varying ingredients cause sunscreens to work in different ways. For this reason, sunscreens are broken out into two main categories:

  • Physical sunscreens sit on top of your skin and work like a shield to deflect sunrays. They may be better for sensitive skin. Their ingredients include zinc oxide and titanium oxide.
  • Chemical sunscreens soak into your skin and absorb UV rays like a sponge. They may be less likely to leave a white residue than their physical sunscreen cousins. Their ingredients may include oxybenzone, avobenzone and homosalate.

It’s important to remember that sunscreen use is just one part of overall UV protection. Your sunscreen can’t filter out 100% of UVB rays. That’s why it’s important to consider the activities you’re taking part in and use other precautionary measures.

Whenever you spend time outdoors

  • Use a sunscreen — even when it’s cloudy — every day. In addition to broad-spectrum protection, choose one that’s SPF 30 or higher and water-resistant. Use enough sunscreen to cover exposed skin. It takes most adults about 1 ounce (enough to fill a shot glass) to fully cover their body.
  • Seek shade—under a tree, umbrella or structure—every chance you get.
  • Cover skin with clothing. For instance, consider wearing a long-sleeved shirt and pants instead of T-shirts and shorts, when practical.
  • Slip on a pair of sunglasses that offer 99 to 100 percent UV protection (check the label).

When you’re exercising or playing in water

  • Reapply sunscreen often. Normally, you need to reapply every two hours. But if you swim or if you sweat during exercise, you’ll need to do that more often. No sunscreen is water- or sweat-proof.
  • Remember that water, snow and sand can all reflect UV rays back onto your skin.
  • Keep your sunscreen in the shade or under a towel. Direct sun can harm it.

Don’t forget the derm

Dermatologists can provide you with expert advice on the best sun protection for your skin type. Here are more reasons why you should see a dermatologist.