They may keep your feet cool but some styles could be doing more harm than good.

Flip-flops have always been a popular solution to sweaty, uncomfortable feet in scorching weather - and now they've had a revamp. The most stylish way to wear them this summer is with a kitten heel, according to fashion expert and trend forecaster Angela Baidoo. "It's not a high heel and it's really kind of easy to just slip in and slip out of," she says. However, heel or not, the flip-flop has earned itself a bad rap for lack of support and damaging our feet. Is that fair? "In terms of arch support and joint support, it's not the best style, but people are investing a bit more, getting their flip-flops customised, because it's something that is just so easy to wear," Baidoo says. Podiatrist Dr Helen Branthwaite, who is also chief clinical adviser at the Royal College of Podiatry, says it's "not accurate" to say flip-flops are bad. The problem comes if you go straight from wearing a very structured shoe to wearing flip-flops a lot, she explains. It means your foot is under more strain than normal, which makes you more prone to injury. "The foot does start to change shape and tends to splay a little bit over time," says Branthwaite.