It is a fashion trend endorsed by Hollywood stars Ryan Gosling, Orlando Bloom and Jude Law.
But the current style of wearing shoes without socks means more people are getting athlete's foot.
Britain's College of Podiatry warns the fungal infection, which causes blisters and redness, is more likely to develop when people go sockless as the lining of a shoe will not absorb sweat, letting bacteria grow.
Socks act as a barrier between the foot and the shoe, soaking up sweat and preventing footwear from developing an unpleasant smell.
The foot, which boasts more glands than anywhere else in the body, produces around half a litre of sweat each day.