Flip Flops 101
Flip flops are the most casual form of sandal—basically, little more than a flat sole with a Y-shaped thong or strap that slips between the first and second toe of your feet to hold them in place. Dating back to the ancient Egyptians, flip flops have been popular footwear since WWII after American soldiers brought back the Japanese zori.
Flip flops can be made from a number of materials:
- Polyurethane – This is typically used for the cheapest types of flip flops (the $5 ones you find in Old Navy or Walmart), as the material is very cheap. It’s not the most durable, however, and you’ll find it’s very prone to wear. Your weight will compress the footbed until the sandal is so thin you can feel the ground beneath your feet.
- Plastic Foam – This material is as cheap as PU and only slightly more durable. A lot of children’s flip flops are made from this lightweight foam, which is designed to naturally compress to adapt to the shape of your foot. Durability issues are going to be fairly common with this material.
- Rubber – Rubber is a bit more resistant to compression and wear than plastic foam or PU, so you’ll get a bit more use out of flip flops made with the material. However, rubber has a higher density, so it will be firmer and less supportive than foam or PU.
- Recycled Rubber -- Eco-minded companies are turning old car tires into recycled rubber flip flops. These are fairly durable—after all, they’re made out of the same material as the tires on your car—but because they’re reusing existing materials, they tend to be fairly cheap as well.
- Hemp – Hemp sandals have been in use for centuries, and they’ve become a very popular choice for those who want to be eco-friendly. They offer good durability and solid support, and they are sturdier than the cheapest materials. However, they’re not as comfortable as some of the more absorbent materials.
- Cork -- Now we’re getting into the more expensive materials! Cork offers good support and comfort for your feet, and it’s far more resistant to compression. Typically it’s used only for the footbed, and rubber is used for the outsole to give the material traction. Cork alone will scuff and wear off the outsoles easily.
- High-quality Vinyl – Once you’re paying $20 or more for a pair of sandals, you can expect a higher degree of durability. High-quality vinyl is much more durable than rubber, PU, or foam, but it offers the same amount of comfort and support.
- Leather – High-end sandals are typically made with a leather footbed, sometimes over a cork or rubber insole that offers good cushioning and a rubber or PU outsole. Leather is highly durable and comfortable, and offers your feet good support. Combined with the other materials, it makes for a stylish pair of flip flops well worth the price.
The Dangers of Flip Flops
Yes, you read that right!
Flip flops may be super comfortable and convenient, but they can be a bit of a problem. They can contribute to a number of health issues:
Infections – Your feet are fully exposed with no protection from any of the bacteria, viruses, fungi, or other pathogens floating in the air. Your feet will also get dirtier when you’re walking around, meaning mud, rainwater, stagnant water, dirt, dust, and other pathogen-carrying particles can cling to your skin. If you have open wounds, the pathogens can cause infections, and may slow wound healing. There is also a much higher risk of developing a number of skin conditions and bacterial infections because your feet are exposed to pathogens.
Athlete’s Foot – Not surprisingly, flip flops can increase your risk of developing athlete’s foot. The fungal infection is highly contagious, and it can be picked up when the bare skin of your feet is exposed to contaminated surfaces. Worse, the rubber, plastic foam, or PU surface of your flip flops can be like a breeding ground for the fungi, so no matter how much you try to get rid of the infection, you’ll always be re-contaminated when you slip on your flip flops.
Blisters – This is especially common—and painful—during the “breaking in” phase of wearing the flip flops. Before the material softens, it can be rough and cause friction with your skin. If the friction gets too bad, it may lead to blisters. When the blisters pop, not only will it continue to be painful when the strap rubs against the raw, exposed flesh, but you’re also more susceptible to infections.
Toe Malformations – When you wear sandals, you have to use your toes to grip the strap and the footbed tightly as you walk. This is unnatural, and the constant contraction of your toe muscles can actually cause problems with your feet. Hammertoe—the inward bending of your toe knuckles—is a problem far more common among flip flop users.
Improper Movement – Did you know that you take shorter steps when you walk in flip flops? It’s all due to the fact that you’ve got to grip the shoes tightly, so you can’t move with your proper stride. You’re also more prone to tripping over the front of your flip flop, a problem made even worse by the fact that you lift your feet less when you step. Overall, your movement is far less efficient and precise, which can lead to postural and mobility issues.
Excess Heel Wear – Not only is there less heel support built into your sandals, but you’ll find your heels hit the ground with more horizontal force than vertical force. Your heels are designed to take more vertical impact, but this change of movement can throw off your posture and wear on your bones and joints. Add to that the lack of support and you’re at a far higher risk of heel pain—but also pain in your forefoot, ankles, and knees.
Overpronation – Overpronation is the name given to the inward rolling of the feet when you step. It’s a problem that can seriously affect your stride and gait when you walk or run. When you step onto a spongy flip flop, the sole compresses on the inner side, encouraging that inward rolling. Flip flops are a major contributor to this problem.
Tendonitis – The tendons in your feet work with the muscles to keep your bones properly aligned and your joints moving fluidly. But when you wear flip flops, you use your tendons far more than you would wearing proper athletic shoes. This additional wear can lead to tendonitis, an overuse injury that causes inflammation and pain in your feet.
Bunions – Wearing flip flops won’t cause bunions (bony bumps between the base joints of your big toe), but they can make them worse. Because you’re gripping the thong with your toes, your toes basically have to pull inward. This opens the space between your toe joints to give the bunion room to grow.
Exposure to Toxic Materials – No, your flip flops aren’t radioactive, but they may be made with materials that contain chemicals. For example, cheap plastic foam may contain BPA, which is a suspected contributor to various forms of cancer. People with latex allergies may find that the materials in their sandals trigger an allergic skin reaction or even a more serious anaphylaxis on exposure.
Higher Injury Risk – Not only does the flip flop not offer the support you want for your joints and bones, but it can actually increase your risk of injuries. Ankle sprains are surprisingly common with flip flops, thanks to the fact that they don’t support your ankles if they bend when you step wrong. People are more prone to falling, tripping, or stumbling in flip flops, which may lead to broken bones. According to the Consumer Product Safety Commission, roughly 27,000 injuries were related to flip flops in 2016 alone.
Though comfortable, flip flops clearly have some problems! Does that mean you should avoid them altogether? Heck no. It’s all about knowing when and how to wear them right…
When NOT to Wear Flip Flops
If you want to be safe when using flip flops, here are a few times when you should consider literally ANY other piece of footwear:
Walking – If you’re going to walk, you’ll want footwear that offers better support for your arches, a sturdier platform for your forefoot, and better heel cushioning. Even a pair of thick sandals (like Birkenstocks) will be better than flip flops when you walk around a lot.
Running – It should go without saying, but we’re saying it anyways: don’t run in flip flops! They offer no support or cushioning, and they’ll only increase the strain on your feet. Heck, don’t do anything active in flip flops. If you want open-air footwear, go with strappy sandals, which offer much better support and protection.
Outdoor Work – Working in the garden in your flip flops is not a good idea! Not only is there no protection from the sun (increasing your risk of sunburn), but your skin is far more likely to be exposed to bacteria, viruses, fungi, and other pathogens. Your chance of getting skin infections skyrockets when you’re working outside in your flip flops.
Standing for Extended Periods – Again, this comes down to a lack of arch support and heel cushioning. Long periods of standing can take a toll on your joints, even in proper shoes. Without any kind of support or cushioning, you can do real damage to your body and affect your posture negatively.
Driving – Driving in flip flops can be very dangerous! Not only can the flip flops catch on the underside of the pedal (making it hard for you to hit the brakes in an emergency situation), but they can actually get wedged between the pedal and the floor. Plus, the lack of solid surface means you have to push harder and contract your toe muscles more to work the pedals, leading to excess strain on your toes and feet.
Basically, the only times to wear flip flops is when you’re at the pool, beach, or in public showers, or as inside shoes for carpeted homes. They’re also okay for very short trips out, such as to the store. However, it’s usually better to use sturdier, more supportive footwear.
How to Buy the Right Flip Flops
Finding the right flip flops is crucial if you’re going to wear them regularly. Here’s what you need to know:
- Leather is best. Though more expensive, leather is more durable, less prone to causing blisters, and reduces your risk of infection and irritation. It’s worth spending a bit more to get a good pair of leather flip flops!
- Fit matters A LOT. If your feet dangle off the front, back, or sides of the flip flop, you’re definitely wearing the wrong size. You’ll be exposed to more bacteria, more likely to trip and fall, and will increase wear on your feet. Make sure there’s at least ½ an inch between your feet and the edge of the sandal on all sides.
- Test the thong. Make sure that you test the thong between your toes so you can see how the flip flops feel. If the thong is too short, it will rub against your skin and cause blisters. If the thong is too long, it will let your feet flop around and force your toes to work harder to keep the shoe in place.
- Spend more. Yes, that $3 pair of flip flops is great for your wallet, but what about your feet? You should be willing to spend a bit more to get a pair of flip flops that will offer good cushioning, support, sturdiness, and the right fit.
- Thicker is better – The thicker the heel and sole, the more likely the flip flops are to offer decent arch support, cushioning, and stability.
- Consider podiatrist-designed flip flops. Some models have been designed specifically by podiatrists to be comfortable for your feet, with built-in cushioning (like Orthaheel) and support. They will be pricier but much better for your joints and movement.
- Replace regularly. Buy yourself a new pair of flip flops when you first notice signs of wear and tear, compression, or damage. They’re cheap enough that they can be regularly replaced!
- Find a sturdy footbed. If the flip flops can fold in half, it means they’re made out of cheap materials that will compress too easily. Find a pair that has a sturdy footbed, one made of solid rubber, cork, or leather. That’s the shoe you know will give you good support and stability!
Wearing Flip Flops Right
Knowing how to wear flip flops right is the key to safe movement and healthy joints. Here are some tips to keep in mind as you wear flip flops:
Avoid water – Yes, you read that right. Though flip flops are intended to be worn around water (pool, beach, etc.), it’s better to keep them dry. The rubber or plastic footbed gets slippery and the thong is more prone to painful rubbing when wet.
Use fabric or leather instead of plastic or foam – There is far less pain between the toes when walking longer distances in fabric or leather flip flops.
Increase the friction – Applying a coat of hairspray to the footbed of your flip flops can help to increase friction, making it easier for you to walk without straining your toes. Or, add a moleskin pad or gel dot to increase friction—and, as a bonus, decrease irritation.
Break in new shoes – Just like you’d break in a new pair of sneakers before going marathon running, it’s worth breaking in your new flip flops before you take them out walking or to the beach. Wear them around your house for a few days to get a feel for them and reduce the risk of blisters.
Clean them regularly – Leather flip flops can be cleaned by simply wiping them down with a clean cloth (water ruins leather, so you don’t want to get it wet). For rubber, plastic foam, polyurethane, or high-quality vinyl, use a mixture of baking soda and warm water to clean them. Or, for cheaper flip flops, try running them through the washing machine or dishwasher.
Watch your feet – Seeing as there is very little protection for your feet, you’re at a much higher risk of injury from objects in the street, broken glass, nails, even rocks and small debris. Pay close attention to wear you’re stepping!
Give your feet extra TLC – You’re exposing your feet to direct sunlight, environmental toxins, dirt, dust, and pathogens. It’s important that you take extra care of your feet! Apply moisturizing lotion at the end of the day, and consider using a bit of sunscreen before you go out into the sunlight. Wash your feet regularly, keep your nails trimmed to avoid dirt build-up, and keep a close eye out for any cuts, blisters, or wounds that could get infected.