Do you have more than 11 moles on your right arm? You may be at a higher risk of skin cancer.

A new study has found that having more than 11 moles on the right arm indicates a higher-than-average risk of skin cancer or melanoma.

Counting moles on the right arm was found to be a good indicator of total moles on the body. More than 100 indicates five times the normal risk, according to the study which used data from 3,000 twins in the UK.

Researchers from King's College London studied a large group of female twins over a period of eight years, collecting information on skin type, freckles and moles on their bodies.

After repeating the exercise on a smaller group of around 400 men and women with melanoma, they came up with a quick and easy way to assess the risk of skin cancer, 'the BBC' reported.

Females with more than seven moles on their right arm had nine times the risk of having more than 50 on their whole body.

Those with more than 11 on their right arm were more likely to have more than 100 on their body in total, meaning they were at a higher risk of developing melanoma.

"The findings could have a significant impact for primary care, allowing general practitioners to more accurately estimate the total number of moles in a patient extremely quickly via an easily accessible body part," said lead author Simone Ribero, of the department of twin research and genetic epidemiology at King's.

The study was published in the British Journal of Dermatology.