On The Early Show Saturday, medical contributor Dr. Mallika Marshall went through them, and had some do's and don'ts for wearers of the cool, comfy footwear.
Flip-flops aren't just for the beach anymore. You now see them all over - and on men as well as women.
But Marshall says they don't come without a possible price to the well-being of your feet.
The growing use of the thin-soled, rubber slippers increases chances of serious foot problems, from damage from dropped objects and stubbed toes, to ankle and insole woes caused by their lack of support.
According to Marshall:
Preliminary research from Auburn University shows that the thin soles and the need to grasp the shoes onto our feet force us to walk differently, and could cause problems with legs, knees, hips and backs.
The lack of support offered by flip-flops can cause problems with arches and heels.
Their lack of protection means toes can be badly injured if someone steps on them, or drops something on your foot.
And now, some doctors are warning of a new danger - skin cancer, as the sun is suddenly hits an area that's usually well-covered.
When you wear flip-flops, your toes and feet are exposed, making them susceptible to falling objects or people stepping on your toes. Doctors are seeing more nail injuries and broken or bruised toes, which wouldn't happen if you covered the front of your feet.
Flip-flops don't offer much in the way of support: no arch support, no heel cushioning, and no shock absorption. That can cause foot pain, tendonitis, and even sprained ankles if you trip.
The Auburn study indicates that the thongs in the middle mean you have to grip the shoe to keep it on. The thong can actually rub against the skin and causes ulcerations and sores. Also, when you have a toe thong, you tend to grip the shoe with your toes to try and keep it on. That alters your gait and puts strain on muscles you don't normally use when you walk in regular shoes.
Also, a recent study found that men and women who wear flip-flops actually strike the ground with less force than when they wear sneakers, again altering the way you walk and causing you to take shorter steps, which may account for why people who wear them for extended periods experience lower leg pain and have more heel problems, such as heel spurs (little bony growths on the heel) and plantar strain (inflammation of the sheet of tissue covering the bottoms of the feet).
Your foot skin is exposed to the sun with flip-flops and people often forget to put sunscreen on their feet. Skin cancer on the feet can be really, dangerous because the spots are easier to miss, especially if they're between the toes.
People More Prone To Problems
Anyone with existing foot injuries shouldn't wear flip-flops. People with diabetes, who are at higher risk of infection and toe injury, shouldn't wear them. And anyone who's significantly overweight needs more support in their shoes, because they tend to put more stress on their feet, ankles and lower back.
Decreasing the Dangers
Use sun block and check your feet for any suspicious moles.
Don't walk long distances in your flip-flops - they're really made for walking along the beach or by the pool or if you get into a public shower, not for long strolls.
And choose flip-flops with thick soles, which will provide more cushion for your feet and protect you from sharp objects you might encounter on the street.
So, enjoy your flip-flops, but just not all the time and without giving them any thought!