The 7 Worst Health Habits Ever

What's the big deal? "It's a common misconception that flat shoes are good for your feet," says Megan Leahy, DPM, a podiatrist at the Illinois Bone and Joint Institute in Chicago. "The ballerina-style shoes that roll up and fit in your purse are even worse because they offer no stability or cushioning." A common ailment Dr. Leahy sees when women wear flats that don't offer enough support is plantar fasciitis, inflammation of the thick tissue at the bottom of the foot. Sky-high heel wearers can also face problems, ranging from foot sprains to broken ankles after taking a tumble in them. Wear the wrong shoes for too long and Dr. Leahy says it may lead to prolonged pain, physical therapy, and even cortisone injections.

Break it: It may not win you an award for street style, but Dr. Leahy recommends wearing supportive athletic shoes to and from work. After wearing heels all day, take some time to do a few calf stretches against a wall, especially before hitting the gym. This will relieve some of the tightness in the foot. If pain occurs, take a break from your heels as much as you can and invest in Dr. Scholl's For Her High Heel Insoles ($9.99, drugstores nationwide) for extra heel cushioning, or shoes with built-in arch support, like Cole Haan shoes that are built with Nike Air technology.