Risk

Risk of skin cancer:
These factors may increase your risk of skin cancer:

• Fair skin. Having less pigment (melanin) in your skin provides less protection from damaging UV radiation. If you have blond or red hair, light-colored eyes, and you freckle or sunburn easily, you're much more likely to develop skin cancer than is a person with darker features.
• A history of sunburns. Every time you get sunburned, you damage your skin cells and increase your risk of developing skin cancer. After a sunburn, your body works to repair the damage. Having multiple blistering sunburns as a child or teenager increases your risk of developing skin cancer as an adult. Sunburns in adulthood also are a risk factor.

• Excessive sun exposure. Anyone who spends considerable time in the sun may develop skin cancer, especially if your skin isn't protected by sunscreen or clothing. Tanning also puts you at risk. A tan is your skin's injury response to excessive UV radiation.
• Sunny or high-altitude climates. People who live in sunny, warm climates are exposed to more sunlight than are people who live in colder climates. Living at higher elevations, where the sunlight is strongest, also exposes you to more radiation.
• Moles. People who have many moles or abnormal moles called dysplastic nevi are at increased risk of skin cancer. These abnormal moles — which look irregular and are generally larger than normal moles — are more likely than others to become cancerous. If you have a history of abnormal moles, watch them regularly for changes.