The sun is vital for life on Earth, but it also poses a risk to people, especially when sun protection isn’t prioritized. Ultraviolet radiation from the sun can damage the skin, eyes, and other tissues, leading to premature aging, sunburn, and even cancer.

Wearing sunglasses in the sun and applying sunscreen regularly are simple ways to protect against sun damage. Johns Hopkins Medicine says proper sunscreen use helps prevent most adverse effects of sun exposure. Sunscreen should be part of one’s daily routine, not just something applied before a visit to the beach. The American Academy of Dermatology offers these tips from board-certified dermatologists on the proper use of sunscreen.

  • Use SPF 30 or higher. Choose a sunscreen with a sun protection factor (SPF) of 30 or higher, and look for one that is water-resistant and provides broad-spectrum coverage, which protects against UVA and UVB rays.  
  • Try tinted iron oxide. Sunscreens tinted with iron oxide offer better protection against the development of dark spots. Iron oxide protects the skin from the sun’s visible light. 
  • Apply ahead of time. It takes approximately 15 minutes for sunscreen to be absorbed by the skin and provide protection. Therefore, it’s best to apply it well before heading outdoors.  
  • Don’t be stingy. It’s important to use enough sunscreen. Most adults need at least 1 ounce of sunscreen, which is about enough to fill a shot glass. This helps fully cover skin that is not protected by clothing. When applying sunscreen to the face, use at least one teaspoon. Always rub sunscreen thoroughly into the skin to ensure it is absorbed and evenly distributed. 
  • Recognize that order doesn’t matter. As long as the sunscreen is at least SPF 30, water-resistant, and broad-spectrum, the order of application doesn’t matter. It can be applied before or after other skin care products and makeup. It’s best for a person to figure out what works for their routine. 
  • Know that most ingredients work. Sunscreens are often grouped into two categories: chemical and mineral. Chemical sunscreens use ingredients like octisalate or homosalate, while mineral sunscreens use either zinc oxide or titanium dioxide. Both chemical and mineral sunscreens are effective, but people with sensitive skin may prefer mineral sunscreens, which often leave a noticeable white cast. 
  • Reapply frequently. It’s important to reapply sunscreen every two hours and immediately after swimming or sweating. People who get sunburned often apply too little sunscreen or don’t reapply it enough. 
  • Check the expiration date. Sunscreen expires and can become ineffective. If the sunscreen has been sitting for a while, it’s probably best to toss it and buy a new bottle. 

Skin is exposed to harmful UV rays every time a person goes outside — even on cloudy days and in winter. It is essential to make sunscreen application part of a daily wellness routine.