Hairy Body Man
Singer Miley Cyrus this week shocked fans with this photo by challenging convention - and leaving her underarms unshaved
HOW BODY HAIR HELPS YOUR SKIN HEAL
Hair anywhere on the body is important for maintaining skin health, explains Des Tobin, a professor of cell biology at the University of Bradford.
'Each hair follicle [the tiny structure that sprouts hairs] is not just producing a hair fibre, but also has masses of blood vessels, nerves and fat around it.'
Hair follicles are also rich in stem cells - cells that never lose the capacity to renew themselves - which help the skin heal.
'If you compared a wound on the outside of a man's arm, where the hair follicles are larger and more numerous, with a wound on the inside of the arm, the one on the outside would heal better, because of the increased stem cells and blood supply, among other factors, ' says Professor Tobin.
Similarly, a bald scalp is less able to cope with nicks, cuts and bruising than a hairy one because of the lack of healthy follicles. As we age, follicles shrink and while people who lose hair will still have some stem cells, their healing capacity may be reduced.
The good news is that removing hair through shaving or waxing won't reduce these benefits because the hair follicles are still intact.
Body hair harks back to our prehistoric ancestors - it was our only garment, keeping us warm and protecting us from environmental impact such as sunlight, explains Nick Lowe, consultant dermatologist from London's Cranley Clinic.
While few of us have dense enough hair to serve this purpose now, someone who's particularly hairy may have an extra degree of sun protection, he says.
Another historic function of body hair was to keep us warm, says Professor Tobin, who is also director of the Centre for Skin Sciences. 'We do know bald heads lose more heat, and that when we're cold, our body hair stands on end to trap warm air closer to the surface of the skin.'