Skin cancer is the most common cancer in the United States. More cases are diagnosed each year than all other cancers combined. And most of them are preventable.
When it comes to sun protection, there is a lot of confusing information out there: which SPF to use, which type of sunscreen is best, how often to reapply, whether clouds actually protect you. It adds up to a lot of reasons to put it off.
This July, for UV Safety Awareness Month, we want to cut through the noise and give you a practical guide, written from a primary care perspective.
Table of Contents
What is UV radiation?
UV damage adds up in ways that go beyond a sunburn. Repeated UV exposure damages the DNA in skin cells, and over time that damage can lead to skin cancer. The three main types are:
- Basal cell carcinoma, the most common form, which grows slowly and rarely spreads but can cause significant local damage if untreated.
- Squamous cell carcinoma, which develops in the outer skin layer and can spread if not caught early.
- Melanoma, the least common but most dangerous type, known for spreading quickly to other parts of the body.
Other effects worth knowing about
- Photoaging. UVA rays break down collagen and elastin, leading to wrinkles, sagging, and age spots well before a person’s natural aging process would cause them.
- Cataracts. UV exposure to the eyes over many years is a leading cause of cataracts, a clouding of the eye’s lens that can affect vision.
- Immune suppression. UV radiation can weaken the skin’s immune response, making it harder for the body to detect and repair damaged cells, including precancerous ones.
Protecting your skin isn’t just about avoiding a burn today. It’s about reducing risk that builds up over a lifetime.
Who is at risk?
Everyone. UV radiation affects all skin tones, not just fair skin. While individual risk levels vary, no one is immune to the effects of cumulative sun exposure.
A few facts worth knowing:
- One in five Americans will develop skin cancer by age 70.
- Sun damage builds up over a lifetime. Only about 23 percent of your total lifetime UV exposure happens before age 18.
- Using a tanning bed before age 35 increases the risk of melanoma by 75 percent.
- Outdoor workers, children, and athletes face higher daily exposure and need to be especially consistent with protection.
Who faces higher risk
Some people need to be more vigilant than others, including those with:
- Fair skin, light eyes, or light hair, which means less natural protection from UV damage.
- Family history of skin cancer in a parent or sibling.
- A weakened immune system, making it harder for the body to repair UV damage and catch abnormal cells early.
- Photosensitizing medications, like some antibiotics and acne treatments, which increase UV sensitivity.
- Outdoor occupations, such as construction, landscaping, or farming, with regular cumulative sun exposure.
- A history of blistering sunburns, especially in childhood.
Knowing where you fall on this list can help guide how closely you monitor your skin and how strict your sun protection should be.
Understanding the UV Index
The UV Index is a daily forecast of how strong UV radiation is in your area, on a scale from 1 to 11+. It accounts for both UVA and UVB rays, giving you a single number that reflects your overall risk of sun damage that day. When it reaches 3 or higher, it is time to take active protection measures.
A few things people often get wrong:
- UV rays are present even on cloudy days.
- They reflect off water, sand, snow, and cement, which can intensify exposure.
- They are strongest between 10am and 4pm, regardless of how hot it feels outside.
You can check the UV Index on most weather apps or at weather.gov.
Five ways to protect your skin
These are the five things that actually make a difference, based on what primary care providers and dermatologists consistently recommend.
Wear broad-spectrum sunscreen every day
Use a sunscreen labeled broad-spectrum with an SPF of 15 or higher. Daily use reduces the risk of developing melanoma by 50 percent and squamous cell carcinoma by about 40 percent. Apply it 15 minutes before going outside and reapply every two hours, or after swimming or sweating. No sunscreen is truly waterproof. Even water-resistant formulas only protect for 40 to 80 minutes in water, so reapplying afterward still matters.
Seek shade during peak hours
UV rays are strongest between 10am and 4pm. When you are outdoors during those hours, shade makes a real difference. Umbrellas, trees, and covered structures all count.
Cover up
Wear clothing that covers your arms and legs when practical. A wide-brimmed hat that shades your face, neck, and ears adds meaningful protection. Look for clothing with a UPF (Ultraviolet Protection Factor) rating if you spend significant time outdoors. UPF measures how much UV radiation a fabric blocks, similar to how SPF works for sunscreen, so a higher number means better protection.
Protect your eyes
Wrap-around sunglasses that block both UVA and UVB rays protect not just your eyes but the delicate skin around them. UV exposure is linked to cataracts and eye conditions that develop over time.
Skip the tanning bed
Indoor tanning devices can emit UV radiation at levels 10 to 15 times higher than the sun at peak intensity. There is no safe level of tanning bed use. If you have used tanning beds in the past, mention it to your provider at your next wellness visit.
Sunscreen explained simply
Sunscreen labels can be confusing. Here is what actually matters.
SPF stands for Sun Protection Factor. SPF 15 blocks about 93 percent of UVB rays. SPF 30 blocks about 97 percent. Consistency of application matters more than chasing a higher number.
Broad-spectrum means the sunscreen protects against both UVA and UVB rays. Always choose broad-spectrum.
Chemical vs mineral: chemical sunscreens absorb UV rays and convert them to heat. Mineral sunscreens (zinc oxide or titanium dioxide) sit on top of the skin and reflect UV rays. Both work. Mineral formulas tend to be gentler for sensitive skin.
How much to use: most people do not apply enough. Aim for about one ounce, roughly a shot glass full, to cover your whole body.
How your primary care provider can help
Sun safety is not just a dermatology conversation. Your annual wellness visit at Altea Medical is a good opportunity to talk about skin health, especially if you have had significant sun exposure over the years, a history of sunburns, or a family history of skin cancer.
During a wellness visit, your provider can:
- Review your personal risk factors for skin cancer
- Perform a basic skin check as part of your physical exam
- Refer you to a dermatologist if anything needs a closer look
- Help you build a sun protection routine that fits your lifestyle
Early detection changes outcomes significantly. When melanoma is caught early, the five-year survival rate is over 99 percent. When it has spread to distant organs, that number falls to 35 percent. Catching things early is the whole point.
When to see a doctor about your skin
Do not wait for your annual visit if you notice any of the following:
- A mole that has changed in size, shape, or color
- A new growth or sore that does not heal
- A spot that bleeds without an obvious injury
- Anything that looks or feels different from surrounding skin
A helpful tool is the ABCDE rule:
- Asymmetry: one half of the mole does not match the other
- Border: irregular, ragged, or blurred edges
- Color: uneven coloring or multiple shades of brown, black, red, white, or blue
- Diameter: larger than a pencil eraser, about 6mm
- Evolving: any change in size, shape, or color, or a new symptom like bleeding or itching
You do not need a dermatologist referral to start the conversation. Your Altea Medical provider can assess your concerns and refer you if needed.
Frequently asked questions
Medical disclaimer: This post is for general informational purposes only and is not intended to replace the advice of a qualified healthcare provider. Please speak with your doctor or a member of your care team for personalised medical guidance based on your individual health history and circumstances.
