Limiting sun exposure isn't the only way to protect your skin.

You don't need a red, peeling sunburn to know that too much UV exposure isn't good for your skin. By now, we’re all familiar with the fact that too much sun on too many occasions could set us up for cancerous consequences down the line—and many of us are diligently slathering on the SPF to combat that risk.

“Each blistering sunburn is important,” explains Susan Y. Chon, MD, associate professor in the department of dermatology at the University of Texas MD Anderson Cancer Center. Intense sun exposure that results in a blistering burn increases a person’s risk of melanoma, the deadliest form of skin cancer, she says.

But sun exposure isn’t the only skin cancer risk factor. Here are some other traits and habits linked to the disease you should know about.

Light skin, hair, and eyes

The lighter your skin color, the less natural protection you have against UV rays, Dr. Chon says. People with blue or green eyes or blonde or red hair also have a higher risk of skin cancer than people with darker eyes and hair. Sorry, redheads: You have the highest risk of melanoma, according to the National Council on Skin Cancer Prevention.

If you have darker skin, you’re more likely than your lighter-skinned friends to encounter skin cancer on paler areas of your bodies, like the palms of your hands and the soles of your feet, Dr. Chon says.

A family history of skin cancer

If you come from a long line of light-skinned redheads or devoted tanners, there may be incidences of skin cancer among your relatives that can serve as a warning sign to you. But there are also some genetic risks for melanoma, including mutations linked to pancreatic cancer and breast cancer, says Dr. Chon. “They’re not common enough that we would screen someone,” she explains, but if you know these genes run in your family, you might be more proactive about sun protection.

Certain genetic conditions that run in families—like xeroderma pigmentosum—also increase your risk of skin cancer.

A history of indoor tanning

Tanning beds and lamps obviously aren’t exposing you to natural sunlight—but they are still exposing you to ultraviolet light, the damaging rays that tan and burn your skin. According to the American Academy of Dermatology, indoor tanning could very well be responsible for some 400,000 skin cancer cases each year in the U.S.

Your age

Skin cancer can occur at any age, but your risk increases as you get older, since you’ve had more time to accumulate UV exposure. There can be quite a lag between your blistering childhood sunburns and a skin cancer diagnosis: People usually find non-melanoma skin cancers in their late 50s, Dr. Chon says. "It takes time for [skin cancer] to become a problem,” she says. "Whatever you can do to decrease how much sun exposure you’re getting delays the onset of skin cancers."

Your sex

Men are more likely to have all three of the major categories of skin cancer. Compared to women, they’re twice as likely to have basal cell skin cancer, about three times as likely to have squamous cell skin cancer, and more likely to have melanoma too, according to the National Council on Skin Cancer Prevention.

The number of moles you have

Moles—those slightly funnier-looking, freckle-like skin spots—are usually not cancerous, but if you’re covered with the marks, you might have a higher risk of skin cancer. Here’s a helpful trick: Count up the number of moles you can spot on your right arm. If you see 11 or more, you probably have more than 100 across your whole body—a risk factor for melanoma, according to a 2015 study.

Too many to count? You’re probably a good candidate for regular skin exams with a dermatologist. "Patients who have a lot of moles are usually under more surveillance," Dr. Chon says. That can include routine skin screenings and taking photos of moles to keep an eye on how they change over time.

A weakened immune system

When your body’s defenses are down, you’re more likely to develop skin cancer. Your immune system might be suppressed by certain diseases or medical treatments, according to the American Cancer Society, like after an organ transplant, when patients usually take meds that prevent their bodies from rejecting the new organ.