Please note: This article is not about extolling the virtues of flip-flops vs. other footwear for people who usually wear shoes. This article is for people who normally live barefoot, and in that context may occasionally need some temporary footwear when being barefoot may not be possible or practical.
Being barefoot is the most natural and healthiest way for humans to live, as the human foot was never designed to be be closed up in restrictive shoes. Shoes in fact are the cause of at least 90% of all foot problems suffered by people.
Some kind of ‘footwear’ may be needed for special purposes at times
Of course, there are some times and occasions that some type of footwear needs to be worn – whether that need is due to weather conditions or due to some arbitrary and unreasonable “requirement” of some facility we may need to enter, with no other choice or option.
The simple flip-flop is the very closest thing to actually being barefoot that is generally accepted as being “shoes” in our modern society.
Flip-flops are a simple sandal, and date back to ancient times
Flip-flops are a type of sandal, consisting of a flat sole held loosely on the foot by a Y-shaped strap between the first and second toes and around both sides of the foot near the front. This style of footwear, thong sandals, has been worn for thousands of years, dating back to pictures of them in ancient Egyptian murals from 4,000 BC.
In the United States, the flip-flop evolved from the Japanese zori, which became popular after World War II as soldiers brought them back from Japan. They became popular footwear in the U.S. starting in the 1960s, first worn mainly by women, then gradually adopted by men as casual dress in general became more popular.
Flip-flops, worn all over the world, may be referred to by different names
Today, flip-flops are worn regularly by billions of people around the world, either seasonal or year round, especially in countries with generally warm climates.
Flip-flops are called different things in different places, and that has also changed over time. When they first appeared as a product for sale to the public, sometime in the late 1950s, they were called “shower shoes,” and were basically meant to wear when taking a shower, especially in a place that wasn’t so clean.
In Hawaii, where I first saw them actually being worn in public many years ago, they were called “slippers,” and I think they are still called that there. When they later became popular with the mainstream public on the U.S. mainland, manufacturers began referring to them as “thongs,” and that’s the name they went by for many years.
Then, as fashion inevitably changes, somewhere around the early 1990s, a very skimpy style of women’s underwear began becoming popular. It was based somewhat on the string bikini swimsuit, and manufacturers began referring to those skimpy female panties as “thongs.”
“Thongs” as underwear became more and more popular, so there began to be a confusion in terms. Most people then, hearing the word “thongs,” began to think of women’s skimpy underwear, not footwear.
So, to alleviate the confusion, the term “flip-flops” came into existence to refer to the footwear, and the word “thongs” as referring to footwear became a rare use of the term for most Americans.
Some other countries of the world, such as Australia, continue to this day referring to flip-flops as “thongs.” Other countries of the world use even different terms to refer to flip-flops, such as “jandals” in New Zealand.
Flip-flops started being worn and accepted in the U.S. around 1960
When I got out of the Navy, in the early ‘60s, I wore them often outside of work, but very few men at that time – except hippies – would ever appear in public wearing sandals, much less the flimsy flip-flop type of sandals.
Around that time and before, anyone needing a break from wearing regular shoes would simply go barefoot. Being barefoot at that time was quite common, especially among teenagers and young adults, and did not have the negative stigma that we sometimes see today.
Flip-flops have seemed to replace barefooting over the years
As flip-flops became more popular and accepted by society, more and more people who might otherwise have chosen to simply be barefoot began wearing flip-flops in public.
Interestingly, the popularity and acceptance of wearing flip-flops in public paralleled the decline of people being barefoot in public. It can be argued that current flip-flop wearing indeed has been the main reason very few people can be seen going barefoot in public nowadays.
Back when people’s only choice was to either wear closed shoes or go barefoot, a lot of people chose being barefoot. There was just nothing else, since sandals or flip-flops just were not worn by anybody in public. If somebody did, they would be stared at and thought of as kind of weird (kind of like what happens now when you go barefoot in public).
Flip-flops are the closest footwear to actually being barefoot
Flip-flops are the closest footwear to actually being barefoot for the following reasons:
1. Almost all the foot remains bare and open to fresh air and light. The only part that is consistently in contact with the skin is the thin strap (usually about 1/2 inch in diameter) between the first and second toe and around the front part of the foot.
The sole of the flip-flop comes into direct contact with the bottom of the foot only during the step-down phase of the gait when the body weight comes down on each foot.
But with flip-flops, that’s only momentarily, unlike regular sandals that are strapped tightly to the foot front and back, forcing the foot to constantly remain in contact with the sandal sole. During the other part of the gait with flip-flops, the foot is off the ground and the sole is only loosely hanging on by the front strap between the toes.
2. Flip-flops can be easily just slipped off the foot when not needed to be on the foot. In other words, if just sitting, a flip-flop can be removed without even touching it – and then slipped back on when needed, again without even touching it.
3. Since flip-flops aren’t bound or strapped to the feet – like shoes or regular sandals – the feet are free and unfettered and are able to use all their muscles as needed for each step when walking. That includes unique and subtle movements of the toes at certain points during the gait to keep the flip-flop from sliding off the foot.
The internet abounds with articles condemning flip-flops with blatantly false or misleading statements
A strange phenomenon has occurred in recent years on the internet with numerous articles strongly condemning flip-flops and the wearing of them. Most of these articles include false statements and allegations of how flip-flops damage the feet and other body parts. These statements have no basis in fact or legitimate scientific studies whatsoever, and apparently are based only on personal bias.
Negative statements against flip-flops may also come from a veiled economic interest. Flip-flops are cheap – manufacturers make much more profit selling shoes. Flip-flops also don’t damage feet like long-term shoe wearing does – podiatrists make more money treating feet that regularly wear shoes, not flip-flops (and certainly not bare feet).
Here are a few examples of the false or misleading statements being made in various internet articles about flip-flops. These few statements below were directly copied from one article I saw, but certainly do not represent all or the extent of flip-flop “horror stories” that can be found published on the internet – some listing almost every foot ailment known to mankind and blaming flip-flops for causing them. Almost none of the foot ailments attributed to flip-flop wearing can be backed up by empirical evidence, known scientific studies, or even basic logic.
(1) “Scarce support: If you plan to walk with flip flops on, it could turn out to be painful for you in the long run, since they have no heel cushioning, no arch support and no shock absorption.”
Those attributes – no heel cushioning, no arch support, no shock absorption – are in fact the advantages of flip-flops. That’s why they are similar to being barefoot, and therefore help make your feet stronger and more natural.
(2) “Little protection: Flip flops give your feet little protection in terms of keeping them away from the harsh sun rays or saving them from insect bites. You’re probably going to be left with sunburned toes. They also leave your feet exposed to bacteria and fungal infections.”
No protection from the “sun” or “insect bites”? That’s almost laughable as an excuse to not wear flip-flops.
As to exposed to bacteria and fungal infections, exposure to bacteria or fungi is not what causes infections. Bacteria and various fungi are everywhere, including on human skin at all times. Bacteria or fungi will not survive, grow, and infect unless it is closed up in a dark, damp place like a closed shoe. A flip-flop does not provide the unique environment needed for bacteria or fungi to grown and infect a human foot.
(3) “Lead to bad posture: Flip flops mess with our posture as they are extremely flat. They don’t bend like our foot and tends to alter the biomechanics, which in turn affects our posture.”
No, flip-flops don’t “bend like our foot.” They don’t need to. With flip-flops, the foot is not locked down or strapped to the sole like they would be with shoes or regular sandals, so as each step is made, the foot is free to naturally bend on its own.
“Altering biomechanics” is just nonsensical babble, and flip-flop walking has no negative effect on posture any more than any other footwear does.
(4) “Destroys the heel: With flip flops on, your heel hits the ground with a lot more force with nothing to protect it except a thin piece of sole. “The heel-strike impact increases when you walk in flip flops for a long time and can cause pain.”
This is similar to the myth that walking barefoot with a heel strike is unnatural and will damage the body. Nothing could be further from the truth. The fact is that since flip-flops have no built up heel, the heel of the foot will come down closer to the surface with each step, which is the way the human foot was designed to walk.
Claiming the heel will “hit the ground with a lot more force” in flip-flops than with shoes is simply a false statement, as – similar to being barefoot – without the built up heel, people just naturally will make the initial contact with each step in a softer, gentler manner.
(5) “Damage to toes: Wearing flip flops could lead to hammertoe, where the knuckles of the toes have bent permanently. This happens because your knuckles work harder to grip the flip flops and to hold them on your foot.”
This is a ridiculous and blatantly false statement.
Hammertoes are caused by closed shoes that are too tight against the toes – not by flip-flops.
From the Mayo Clinic:
High-heeled shoes or footwear that’s too tight in the toe box can crowd your toes into a space in which they can’t lie flat. This curled toe position might eventually persist even when you’re barefoot.
“Gripping” something with the toes does not cause hammertoe, any more than gripping something with the fingers will damage and distort the fingers. Gripping something with toes or fingers is just a natural movement of the muscles there for that purpose.
“Gripping” is not even an accurate term for what the toes do to hold on flip-flops. The toe movement is only a slight downward pressure for a split second as the foot in back lifts off the ground during the gait.
I’ve also seen much more exaggerated terms used such as “clenching,” “clawing,” or “scrunching” of the toes to hold flip-flops on. Nothing of such extreme nature ever occurs.
This is what really happens to the foot and toes when walking in flip-flops
I wanted to see for myself exactly what my toes were doing while wearing and walking around in flip-flops. So I went and found one of my old pairs of flip-flops, walked all around in them, and carefully observed exactly what my toes were doing as I walked.
These are my observations as I walked:
- My toes are generally relaxed on the front foot that I’m stepping down with.
- Since the flip-flop is at a very slight upward pointing angle as I step down, there’s no need to hold it on my foot – gravity takes care of that.
- Upon stepping down and making contact with the floor, I lift the other foot (in back) off the ground.
- I notice at that point I have to apply a slight downward pressure onto the flip-flop with my toes on that foot as that foot lifts up behind me.
- That’s because during that brief downward angle of the foot, the weight of the flip-flop has a tendency to slip forward out of place on my foot.
- That downward pressure with my toes is kind of gently pressing – not exactly gripping, and certainly not “clenching” or “scrunching.”
- It is only a slight downward push with my toes which is causing the top part of my foot to press more strongly against the straps of the flip-flop – thus, in effect, briefly tightening the pressure both below and above that part of my foot to keep the flip-flop from sliding forward.
- And then when that foot touches down, I relax the toes, and the process begins again with the next step.
- So it’s a gentle flexing and relaxing of the toes as I step.
- Not a lot different from what the toes are doing when we walk barefoot.
- In any case, it’s just exercise for the muscles of the toes.
I can’t see any way whatsoever that these movements as I walk with flip-flops could ever cause any harm.
Actual scientific studies of flip-flop wearing show no evidence of damage to feet or toes
There have been a few actual scientific studies related to flip-flop wearing. None of them have ever proven or shown that flip-flop wearing is in any way harmful to the feet or the toes as is alleged by numerous internet articles and claims. These studies are listed below along with conclusions reached:
- The most well-known and quoted study was done in 2009 at Auburn University: “Influence of Various Thong Style Flip-flops on Gait Kinematics and Lower Leg Electromyography“
They found that flip-flop wearers took shorter steps, and their heels hit the ground with less vertical force than those wearing athletic shoes.
From the study,
In conclusion, no flip-flop investigated was exactly like walking barefoot; however, certain structural components of flip-flops do result in a gait similar to walking barefoot. Future research is still needed to investigate and design a flip-flop that results in a gait identical to walking barefoot.
- A 2019 study published in Gait & Posture, March 2020, “Flip-flops do not alter the neuromuscular function of the gastrocnemius muscle and tendon during walking in children,” found the difference between children walking or running in flip-flops vs. barefoot was negligible to their muscular development.
- This 2013 study published in Journal of Foot and Ankle Research, March 2013, “Effect of thong style flip-flops on children’s barefoot walking and jogging kinematics, ” compared the effect of children walking or running in flip-flops vs. barefoot, and found that “foot motion whilst wearing thongs may be more replicable of barefoot motion than originally thought.”
- This 2015 study published in Gait & Posture, September 2015, “Barefoot vs common footwear: A systematic review of the kinematic, kinetic and muscle activity differences during walking,” looked at anatomical and gait differences comparing shoes, flip-flops, and bare feet.Some of the more significant conclusions reached were that “long term use of footwear has been shown to result in anatomical and functional changes including reduced foot width and forefoot spreading under load probably due to the constraints of the shoe structure” and “lighter and more flexible footwear [flip-flops] appears to elicit reduced differences in gait kinematics to walking barefoot.”
- In a 2008 article in the Journal of the American Podiatric Medical Association, Sept.-Oct. 2008, “Computerized analysis of plantar pressure variation in flip-flops, athletic shoes, and bare feet,” the researchers set out to determine how flip-flops change peak plantar pressure while walking, and “compared peak plantar pressures in the same test subjects wearing flip-flops, wearing athletic shoes, and in bare feet.”What they found was that “flip-flops always demonstrated higher peak plantar pressures than athletic shoes but lower pressures than bare feet.”
That finding would seem a “no-brainer.” Of course shoes are going to soften the impact on the soles of feet (plantar area) when walking, and flip-flops would also, but not as much as shoes. And bare feet would experience the least amount of softness upon impact. As nature intended.
So their published conclusion regarding flip-flops is puzzling: “[F]lip-flops have a minor protective role as a shock absorber during the gait cycle compared with pressures measured while barefoot, [but] they increase peak plantar pressures, placing the foot at greater risk for pathologic abnormalities.”
The term “pathologic abnormalities” is unexplained, and I doubt can be explained with any accuracy or factual demonstration of reasonableness of prognosis. Therefore I see that study as rather simplistic at best, and seriously flawed at worst, based on their poorly defined conclusion.
Flip-flops can be hazardous and accident-prone, but that’s their only disadvantage
I do agree with one of the legitimate criticisms of flip-flops – that they are inherently a little riskier to wear than regular shoes as related to slipping or getting caught on something, which is due to their design.
On the other hand, it is their unique design that makes them an excellent choice to wear instead of shoes if or when “shoes” must be worn on occasion instead of remaining barefoot. Any increased risk of having an accident is exceedingly small, especially when compared to the negative effects of wearing closed-toe shoes as an alternative.