Although humans may look less hairy than apes, we have almost as many hairs on our body as they do. People have about 60 hairs per square centimeter of skin. Many of these hairs are barely visible fuzzy hairs called vellus hair.

Only a few parts of your skin don’t grow hair, including your lips, palms, and the soles of your feet. Although some people say that masturbating will cause hair to grow on your palms, there’s no scientific basis for this myth.

An extremely rare genetic disorder may cause hair growth on your palms. However, it’s so uncommon that’s only been documented a handful of times in history.

Despite rumors you may have heard, masturbating does not cause you to grow hair on your palms. It’s one of many false old wives’ tales about masturbating. It’s not clear where this myth started, but it probably goes back to the Dark Ages as a way to discourage people from masturbating.

Despite the many myths about masturbation, there are no known physical side effects. Some other myths that you may have heard include:

For the vast majority of people, it’s impossible to grow hair on the palms of your hands or soles of your feet. There are a few rare situations where it may occur.

A 1976 article published in the Archives of Dermatology describes a man who grew hair on one of his palms. When the man was a child, he severely injured his right hand. He lost his pinky and some of the skin on his palm. A surgeon used skin from his lower abdomen as a graft for the injury. When he became an adult, the skin graft grew hair.

A rare condition called circumscribed hairy dysembryoplasia of palms can cause hair to grow on both of your palms. The condition is an inherited condition caused by a dominant gene. However, it’s so rare that it’s only been documented a handful of times in the medical literature.

In a 1975 study, researchers described one case of this condition. Four generations of a French-Canadian family had small areas of hair-follicle containing skin near their wrists. According to the researchers, there was only one other scientific study that had documented a similar condition published previously.

The 1973 study describes a French family in which four generations of people had hair on both palms. The family members included a man, his mother, his maternal grandfather, and one of his daughters.

Hair grows from hair follicles located below the surface of your skin. Hair follicles originate in the deep layer of skin called your dermis or in the deeper subcutaneous tissue. Hair can only grow in places where there are hair follicles. Almost every part of your skin has hair follicles except for the soles of your feet, the palms of your hands, and your lips.

A 2018 animal study found that hairless parts of the skin of mice produce an inhibitor called Dickkopf 2 (Dkk2). Dkk2 inhibits a protein called Wnt. Wnt is a signaling protein that’s needed for the development of hair follicles.

More research is needed to see if the same pathway extends to humans.

For the vast majority of people, it’s impossible to grow hair on your palms. Hair grows from hair follicles. There are no hair follicles on your palms unless you have an extremely rare genetic disorder called circumscribed hairy dysembryoplasia of palms.

Despite the prevalent myth, masturbating doesn’t cause you to grow hair on your palms. There are no known physical side effects of masturbating.