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AP Photo/Rick Bowmer
Hypochondriacs, beware.

The moles on your right arm may predict your risk of skin cancer

By Amy X. Wang

Melanoma, the skin cancer that develops from irregular moles, is a particular concern for people who have many freckles and blemishes. New research now suggests that it’s specifically those with 11 moles or more on their right arms who need to care the most.

Medical researchers from King’s College London, funded by the Wellcome Trust research charity, recently published a study in the British Journal of Dermatology that says the right arm is a predictive area for how many moles a person has on his or her entire body. Since having more moles overall puts you at greater risk for melanoma, one rough way to estimate your risk is by counting the moles on that arm.

Though only half of melanomas develop from existing moles, these cases are often hard for unsuspecting patients to catch by themselves. The study’s results may make it easier to understand one’s chances: By examining more than 3,500 female twins and then repeating the exercise on a group of roughly 400 men and women, researchers found that people with more than seven moles on the right arm were likely to have more than 50 moles on the whole body.

People with more than 11 moles on their right arms were likely to have more than 100 overall—a number that the researchers deemed indicative of “significant risk” for melanoma.

Simone Ribero, the study’s lead author and a researcher in the field of genetic epidemiology, suggested in a university press release that the findings could have an “impact for primary care, allowing [doctors] to more accurately estimate the total number of moles in a patient extremely quickly via an easily accessible body part.”

Having a high number of moles isn’t the only risk factor for melanoma. If you have red hair, fair skin, or have been badly sunburned in the past, you should probably schedule a cautionary visit to the dermatologist, too.