Arizona has some of the highest ultraviolet levels in the United States, and Arizona’s skin cancer rates are among the highest in the country. The essentials: broad-spectrum SPF 30 or higher applied generously and reapplied every two hours, shade between 10am and 4pm, a wide-brimmed hat, sunglasses, and a check of your own skin once a month. Anything changing, growing, or refusing to heal deserves an appointment.
Our UV index regularly reaches levels described as “extreme” — and it does so in spring and autumn too, not only high summer, which is when people let their guard down.
Check your own skin monthly
Most skin cancers are found by the person who lives in the skin. Once a month, in good light, with a mirror for your back, work through: face, ears, scalp (part your hair), neck, chest, back, arms, hands and nails, legs, feet including the soles and between the toes.
For moles, use ABCDE:
- A — Asymmetry. One half does not match the other.
- B — Border. Edges are ragged, notched, or blurred.
- C — Colour. More than one colour, or uneven colour — brown, black, tan, red, white, blue.
- D — Diameter. Larger than about 6mm, the width of a pencil eraser — though melanomas can be smaller.
- E — Evolving. Changing in size, shape, colour, or sensation. This is the most important one.
Also worth an appointment: a sore that does not heal within a few weeks, a pearly or waxy bump, a flat scaly reddish patch, a firm red nodule, a new dark streak under a nail, or any spot that itches, bleeds, or crusts repeatedly. And the “ugly duckling” sign — a mole that simply looks unlike all your others.
Take photos with a ruler or coin in frame. Change over time is the signal, and memory is unreliable.
The three main types
Basal cell carcinoma — the most common. Usually a pearly bump, a flat scaly patch, or a sore that will not heal, on sun-exposed areas. Rarely spreads but grows locally and needs removing.
Squamous cell carcinoma — a firm red nodule, or a scaly crusted patch. More likely than basal cell to spread if neglected.
Melanoma — much less common but responsible for most skin cancer deaths. Can appear in an existing mole or as a new spot, and can occur on skin that rarely sees sun, including the soles of the feet and under nails. Found early, melanoma is usually curable; found late, it is a different conversation entirely. That gap is the entire argument for monthly checks.
Getting sun protection right
SPF 30 or higher, broad-spectrum, water-resistant. Broad-spectrum matters — it means protection against UVA as well as UVB.
Most people use far too little. A full body application is roughly a shot glass; a face and neck application is about half a teaspoon. Under-applying an SPF 50 gives you far less than 50.
Reapply every two hours, and immediately after swimming, towelling, or heavy sweating. There is no all-day sunscreen.
Do not skip cloudy days. A large share of UV penetrates cloud.
Higher SPF is not proportionally better. SPF 30 blocks about 97% of UVB, SPF 50 about 98%. Going higher buys very little, and encourages people to stay out longer.
Mineral sunscreens (zinc oxide, titanium dioxide) work immediately and suit sensitive skin; chemical ones need about 15 minutes before exposure. Either is fine — the one you will actually use is the right one.
Clothing beats lotion. A wide-brimmed hat, UPF-rated long sleeves, and wraparound sunglasses provide protection that does not wear off. In desert heat, light long sleeves genuinely keep you cooler than bare skin.
Don’t forget ears, the back of the neck, scalp parting, lips (use SPF lip balm), the backs of hands, and feet in sandals. And the left arm and left side of the face — Arizona drivers get measurably more sun damage there, because car glass blocks most UVB but not all UVA.
Myths and trends worth dropping
“I need a base tan to protect myself.” A tan is the visible evidence of DNA damage. It offers protection equivalent to roughly SPF 3 and costs you far more than it gives.
“Tanning beds are safer than the sun.” They are classified as carcinogenic to humans and substantially raise melanoma risk, particularly with use before age 35.
“Sunscreen causes more harm than the sun.” The evidence for skin cancer prevention is strong; if particular ingredients concern you, use a mineral sunscreen.
“Dark skin doesn’t need sunscreen.” More melanin does provide some natural protection, but skin cancer occurs in every skin tone and is more often diagnosed late in people of colour — partly because it is looked for less. Acral melanoma on palms, soles, and under nails is a particular concern.
“I’ll get my vitamin D from tanning.” Vitamin D needs are met with brief incidental exposure, diet, or a supplement. Deliberate tanning is a poor trade, and we can check your level with a blood test.
DIY sunscreen recipes are a genuinely bad idea — they are untested, unstable, and wildly under-protective.
“Sun exposure clears acne.” It masks it briefly with tanning and worsens it afterwards, and several acne medications make skin far more sun-sensitive.
Who should be checked professionally
Book a skin check if you have fair skin, light eyes, or freckle easily; a history of significant sunburns, especially blistering ones in childhood; many moles or unusual moles; a personal or family history of skin cancer; a job or hobby that keeps you outdoors; or a suppressed immune system.
For most Arizona adults, an annual professional skin check is sensible, and more often if you have had a skin cancer before. If you have just moved here from a cloudier state, your skin has not been living in this UV before — the first few years are worth being deliberate about.
Where to go
Book our Medical Clinic for a skin check, to have a specific spot examined, or for a vitamin D test. We can assess lesions, arrange biopsy or dermatology referral where needed, and get you a plan. Call (602) 671-7981. Do not sit on a changing mole waiting for it to declare itself.
Come to our Emergency Room for severe sunburn with blistering over a large area, sunburn with fever, chills, confusion, or fainting, or signs of heat illness alongside it. Severe burns cause fluid loss and can need intravenous treatment. ER: (602) 671-7990.
Related: heat exhaustion vs heat stroke
Related reading
- Psoriasis Isn’t Just Skin — and Treatment Has Changed Completely
- Cancer Screenings: What to Schedule, and When
- Desert Hiking Safety: How Locals Avoid Becoming a Rescue
Sources
- American Academy of Dermatology — Skin cancer detection and the ABCDEs
- CDC — Sun safety
- Skin Cancer Foundation — Skin cancer information
- EPA — UV index