How Sunscreen Helps Prevent Skin Cancer and Protects Your Skin
Today's sunscreen formulas make daily use easier
Today's sunscreen formulas make daily use easier
Key Takeaways
- Daily sunscreen can help lower skin cancer risk.
- Use broad-spectrum SPF 30 to 50 sunscreen.
- Reapply every two hours when outdoors.
Daily sunscreen use is one of the most effective ways to help prevent skin cancer and protect your skin from premature aging. Thanks to advances in sunscreen technology, consumers have more options than ever to find a product that works well for their skin and daily routine.
One recent development is the FDA’s approval of sunscreen products containing bemotrizinol, a UV-filtering ingredient that has been used in Europe and Asia for many years. The approval could expand the range of broad-spectrum sunscreen products available in the United States.
“Sun protection doesn’t have to be complicated,” says Hugh Greenway, MD, a board-certified dermatologist and chair of Bighorn Mohs Surgery and Dermatology Center at Scripps Clinic. “The goal is to find sunscreen that fits naturally into your routine so protecting your skin becomes a habit, not a chore.”
Why sunscreen is important for skin cancer prevention
Finding a sunscreen that fits your lifestyle can make it easier to maintain healthy sun protection habits.
Sun protection isn’t just for summer. Even on cloudy days, ultraviolet (UV) radiation from the sun can damage skin cells. In sunny regions like San Diego, that exposure adds up over time.
“Living in San Diego means we enjoy sunshine year-round, but it also means our skin is exposed to UV radiation year-round,” Dr. Greenway says. That ongoing exposure can increase the risk of skin cancer over time, he says.
Skin cancer is one of the most common cancers in the United States. According to the American Academy of Dermatology, an estimated 1 in 5 people will develop some form of skin cancer in their lifetime. The leading cause is exposure to UV radiation from the sun.
Skin cancer can take several forms. Basal cell carcinoma is the most common type, followed by squamous cell carcinoma. Melanoma is less common but is the most serious form because it is more likely to spread to other parts of the body if not detected early.
Understanding how UV rays affect the skin helps explain why sunscreen and other sun protection measures are important.
UVA vs UVB rays: What’s the difference?
The sun emits two types of ultraviolet rays: UVA and UVB. Each type of ray affects the skin differently.
UVA rays penetrate deeper into the skin and contribute to premature aging, wrinkles and long-term sun damage.
UVB rays primarily affect the outer layers of the skin and are the main cause of sunburn. They also play a significant role in the development of skin cancer.
A history of blistering sunburns can significantly increase the risk of melanoma, the deadliest form of skin cancer.
Why sunscreen works
Sunscreen helps protect the skin from harmful UVA and UVB rays before they can cause damage. Depending on the type of sunscreen, UV rays are either absorbed or reflected away from the skin.
Regular sunscreen use can help prevent sunburns, reduce signs of premature aging and lower the risk of skin cancer.
No sunscreen can block 100 percent of UV radiation or completely prevent skin cancer. Sunscreen works best when combined with other sun protection measures, including seeking shade, wearing sun protective clothing and avoiding peak sun hours when possible.
Choosing the right sunscreen
Sunscreen comes in many forms, including lotions, sprays, sticks and powders. The best sunscreen is the one you will use consistently.
When choosing a sunscreen, look for a broad-spectrum product that protects against both UVA and UVB rays. It should also be water-resistant and have an SPF or sun protection factor between 30 and 50.
Most dermatologists recommend SPF 30 to SPF 50 for everyday use. SPF 30 blocks about 97 percent of UVB rays, while SPF 50 blocks about 98 percent.
Chemical vs. mineral sunscreen: What’s the difference?
One of the most common sunscreen questions is whether to choose a chemical or mineral formula. Both types are effective when used correctly but they work in slightly different ways.
Chemical sunscreens absorb UV radiation and convert it into heat before it can damage the skin. They are often lightweight, blend easily into the skin and may be more comfortable for everyday use.
Mineral sunscreens contain ingredients, such as zinc oxide or titanium dioxide. They protect the skin primarily by absorbing UV radiation, while also reflecting and scattering some UV rays.
Many mineral sunscreens are marketed as zinc-based or mineral formulas. Some products may leave a visible white cast, particularly on darker skin tones.
“A common misconception is that people with darker skin don't need sunscreen, but skin cancer can affect people of every skin tone,” Dr. Greenway says. “While melanin provides some natural protection against UV radiation, dermatologists recommend daily sun protection for everyone.”
The good news, he says, is that many newer sunscreen formulations are designed to blend more easily into the skin and minimize the white cast some products can leave behind.
How to apply sunscreen correctly
Applying sunscreen correctly is important for effective sun protection.
Cover all exposed skin, including commonly missed areas such as the ears, neck, scalp, lips and the tops of the feet.
The American Academy of Dermatology recommends using about one ounce of sunscreen per application, roughly enough to fill a shot glass.
For the best protection:
- Apply sunscreen at least 15 minutes before going outside
- Reapply every two hours
- Reapply after swimming or sweating
- Use a lip balm with SPF to protect your lips
When to get a skin cancer screening
Even with daily sun protection, it is important to pay attention to changes in your skin. Early detection can improve treatment outcomes and increase the likelihood of finding skin cancer when it is most treatable.
People with risk factors such as fair skin, a history of skin cancer, significant sun exposure or a family history of melanoma may benefit from regular skin evaluations. Talk with your health care provider or dermatologist about whether skin cancer screening is right for you and how often it should be performed.
Most skin cancers are highly treatable when they're found early. If you notice a new, changing or unusual spot on your skin, don't ignore it. Talk with your primary care doctor or dermatologist.