From the fashionista news article:
Dr. Gary Prant, a podiatrist at Arbor Foot Health Center in Austin, Texas (and my dad!), advises avoiding wearing them on any trek of considerable distance. He also recommends wearing more supportive flip-flops by brands like Noat, Birkenstock and Teva, but discourages wearing the flimsier versions all together. “Those flip-flops are like going barefoot with little protection for the bottom of your feet,” he says. “They protect your feet from stepping on a sharp stone or piece of metal, but give no support or anything else. I could never recommend them.”
Read more at the link:
https://fashionista.com/2018/08/flip-flops-fashion-trend-summer-2018