Jandals may be the iconic footwear of a Kiwi summer, but an Auckland physio says kids with growing bones shouldn't be wearing them.
Melissa de Jongh, who has a Bachelor of Health Science, Physiotherapy and is the director of Parents Health Haven, has advised that parents should avoid letting their kids wear jandals as they are not good for their growth and development.
"Children only get one chance to develop their bones and their muscles properly and putting people, even adults, in jandals isn't great," she said.
She said that the flip-flopping action in jandals can make kids' muscles work harder at a time when their muscles are trying to develop. It can cause their feet to develop in an unusual and abnormal way.
"The achilles tendons and all the little muscles in the feet have to work a lot harder just the hold jandals on as well as to move it forward.
"For our kids, when their muscles are trying to develop in a normal way, [wearing jandals] can actually create problems down the track."
She said jandals can cause knees and hips to be in poor biomechanical positions, which is not good while kids are growing.
They can also cause foot pain, calf pain, or even knee pain in the future.
She added that we're not supposed to have a gap between our first and second toe.
De Jongh advised that the way parents can help their childrens' growth and development is by buying good, supportive footwear or having them run around in bare feet.
"Choose a sandal that wraps around the foot and stays on without flip-flopping, and make sure the sole of the shoe isn't thin, hard and flat.
"We have a natural arch, so our footwear should have the natural arch in it as well."
She emphasised that parents don't have to spend a huge amount of money on shoes, and that good footwear comes at all prices.
For those who don't want to give up the jandals, de John said you need to be practical about it and using them sensibly.
"They're not walking shoes. You can kick around in them, you can go down to the beach in them. Wear your jandals when you go to a BBQ - but not if you're going for a walk."
Speaking to Huffpost, US podiatrist and Vionic shoe Innovation Lab member Jackie Sutera said jandals' thin, unstructured soles offer no support, and can lead to injuries including sprains, tendonitis, fasciitis, heel pain, bunions, hammertoes or stress fractures.
She also agreed that the injuries come down to your feet working too hard to keep the jandal on.
"Toes, tendons and muscles overgrip as you walk to keep them on your feet," she said.
"There is also no arch support, offering no shock absorption or cushioning."
She added that people are putting themselves at risk for permanent damage.
"Ankle sprains and stress fractures from overuse of these shoes are, I think, the worst," Sutera said. "Not only are they painful but there is usually about 6- to 8-week recovery period where your activity is very limited as you heal."
Dr Priya Parthasarathy, a podiatrist spokeswoman for the American Podiatric Medical Association told the New York Times that she had so many people come through her door this year because of jandals.
"Flip-flops don't provide any support. There's no structure," Parthasarathy said. "Your feet have to work much harder to grip the flip-flop."
However, she added that it doesn't mean people can't wear jandals and that there are benefits to wearing them including when some injure their feet/toes or if their feet start to swell from the heat.
Also, the shoe can protect people from getting athletes foot if they wear them in the shower in locker rooms.