How to Use Sunscreen

Sunscreen is a safe skincare product that is applied to protect skin from the sun’s ultraviolet (UV) rays. There are many types of sunscreen and cosmetic products with sunscreen in them. When used correctly, sunscreen helps protect the skin from sunburn, and it reduces the risk of cancer. However, sunscreen does not block all UV rays from the sun.

Is sunscreen safe?

Expert organizations consider sunscreen a safe, vital tool to help prevent skin cancer. Along with the FDA, the American Cancer Society (ACS) and the American Academy of Dermatology Association (AAD) recommend using sunscreen with SPF 30 or higher along with wearing protective clothing, hats, and sunglasses to protect your skin from harmful UV rays.

Learn more about more ways to protect your skin from UV rays.

How the FDA regulates sunscreen

The US Food and Drug Administration (FDA) is required to monitor sunscreen since it’s considered an over-the-counter drug. The FDA has very high standards during this process that are based on scientific research to be sure the product is safe for public use.

The FDA reviews:

• The ingredients in sunscreen
• How sunscreen is made

Products that meet this safety standard are generally recognized as safe and effective (GRASE).

Ingredients recognized as GRASE

• Minerals: zinc oxide and titanium dioxide
• Chemical: bemotrizinol

These are recognized as GRASE for use in sunscreens by children 6 months or older and adults.

Ingredients the FDA says need more research

The FDA has not reported that any sunscreen ingredients used in the US are harmful to a person’s health. However, the FDA has recommended more research be done on some commonly used ingredients, including ensulizole, octisalate, homosalate, octocrylene, octinoxate, oxybenzone, and avobenzone.

You can read more about these ingredients at the Food and Drug Administration website.

What does SPF mean?

SPF stands for sun protection factor. This number shows the level of protection the sunscreen provides against UVB rays, which are the main cause of sunburn.

• Sunscreens are available with SPFs from 15 to 100+.
• In the US, sunscreens with an SPF below 15 must include a warning that the product has not been shown to reduce the risk of skin cancer or early skin aging. It may still help to prevent sunburn.
• A higher SPF number means more UVB protection.

Applying sunscreen correctly limits how much sun UVB exposure you get based on the SPF you use. For example, 30 minutes in the sun using SPF 30 sunscreen is equal to spending about 1 minute in the sun without sun protection. One hour in the sun wearing SPF 30 sunscreen is equal to spending 2 minutes in the sun without protection.

Higher SPF numbers do mean more protection, but the higher the number, the smaller the difference becomes.

• SPF 15 sunscreens filter out about 93% of UVB rays.
• SPF 30 sunscreens filter out about 97% of rays.
• SPF 50 sunscreens filter out about 98% of rays.
• SPF 100 filter out about 99% of rays.

What type of sunscreen is best?

When choosing a sunscreen product, it’s best to use sunscreen with:

• Broad spectrum protection (against both UVA and UVB rays)
• Physical UV filters, such as zinc oxide or titanium dioxide
• Chemical UV filters, such as bemotrizinol
• Sun protection factor (SPF) values of 30 or higher

Sunscreens are available in many forms, including:

• Lotions
• Creams
• Ointments
• Gels
• Sprays
• Powders
• Wipes
• Lip balms

Some cosmetics, such as moisturizers, lipsticks, foundations, and other makeup items are also considered sunscreen products if they have sunscreen as an ingredient.

When choosing a sunscreen, read the label. Some sunscreen products can irritate the skin. Some labels may provide information about how to test for skin irritation or sensitivity. If your skin becomes irritated, contact your doctor or a dermatologist for ideas about which type or brand might be best for you.

No sunscreen protects you completely from UV rays.

Here's more about what these labels mean and what to check before you use sunscreen.

How should I apply sunscreen?

Always follow the label directions for applying and reapplying sunscreen products. Most experts recommend applying sunscreen generously whether it’s your first time using it for the day or you’re reapplying it.

Follow these tips to get the most out of each application of sunscreen:

• Apply sunscreen to all areas skin that’s not covered by clothing, including your neck, face, ears, scalp, and hairline. Use lip balm with at least 30 SPF to protect your lips.
• If you wear insect repellent or makeup, put sunscreen on first.
• Set an alarm or timer on your watch or phone to remind you to reapply sunscreen at least every 2 hours or more often if needed.

How much sunscreen should I use?

Follow the instructions on the bottle or packaging. Instructions might say to apply liberally or generously. Or you might see a recommended amount to use. Use enough sunscreen to fully cover your arms, legs, neck, face, and any other areas that are exposed to the sun.

When should I apply or reapply sunscreen?

Sunscreen works best when it is applied before sun exposure. It takes about 15 minutes for your skin to absorb sunscreen to get the best protection. Sunscreen needs to be reapplied at least every 2 hours to maintain protection.

Sunscreen can wash off when you:

• Sweat
• Swim 
• Dry off with a towel

Some people may find they need to reapply sunscreen more often regardless of the activity they’re doing outside.

Even with proper sunscreen use, some UV rays still get through. Staying in the shade and avoiding direct sunlight can give you more protection from UV rays.

Consider sunscreen as one part of your overall, year-round skin cancer protection plan, especially when shade and protective clothing aren’t practical. Even if you use a sunscreen with a very high SPF, it’s still important to limit your time in the sun.