All About Calluses, Your Skin’s Natural (And Sometimes Painful) Armour

Calluses, those areas of crusty thickened skin on your hands and feet, are part armour and part liability. Gymnasts obsess about shaving them down; runners worry about keeping them built up. With some smart management, it’s possible to have happy, tough skin that doesn’t give you problems.

Illustration by Sam Woolley.

Why You Get Calluses

A callus is an area of thickened skin that develops where there’s a lot of friction or pressure. This might be where the ball of your foot rubs against your shoe, or where your palms rub against the bar when you’re doing a pull-up. Guitar players even get (and cherish) tiny calluses on the tips of their fingers.

The outermost layer of your skin (the stratum corneum above) is made of dead skin cells. That may sound weird, but it’s how your skin is built. These dead, flattened cells protect the living layers of skin underneath. So when there is extra friction or pressure on your skin, your body responds by creating more cells to join that outer, protective layer of dead skin.

Sometimes, you’ll barely notice the callus. Other times, the thickened part may be so large and lumpy that it causes more problems than it solves. That’s when it’s time to think about removing or thinning that callus, which we’ll talk about later.

The friction that causes calluses can also cause or exacerbate blisters. A blister can form when rubbing causes layers of skin to separate from each other. Because your cells are always surrounded by a clear fluid, some of that fluid fills the space in the separation, and as a result, you get that creepy looking bubble you know and probably hate.

As a newbie runner, say, your sensitive feet may develop blisters on your first long run. But once you’re more experienced, your feet will have literally toughened up: you will have calluses that somewhat protect the skin in that area. The blisters aren’t a requirement, though; blisters do not “turn into” calluses.

It takes a few weeks to build up a callus. If you take a break from whatever caused the callus — you give up running over a long holiday, or you put down the guitar for a while — your skin will stop making the extra dead cells. We lose skin cells constantly, so the callus will fade after a few weeks.

When to File Down a Callus, and When Not To

People have very strong opinions about their calluses. Hop onto any specialised forum — for dancers, roller derby players, Crossfit enthusiasts, violinists — and you’ll see a ton of recommendations about how you should, or why you should not, try to remove them.

To get some perspective on these controversies, I talked to Dr Paul C. Kupcha, section chief of the Foot and Ankle Section in the Orthopaedic Division at Christiana Care Health System in Delaware.

Shaving a callus down, he said, is unlikely to do much damage. Even if you file off too much, you’ll grow it back before long. He’s more concerned about the opposite situation, “letting it get too thick and having too much pressure. Because that callus, that cornified epithelium, becomes rock hard and it’s like taping a pebble to your foot or to your hand.”

Taking care of your skin, then, is a balance between keeping enough callus to protect you, and keeping it thin enough to not become a problem. Here are some of the things that can happen when a callus gets out of control:

• Like a rock in your shoe, a callus can lead to more irritation. It’s possible to get a blister underneath the callus in some cases.
• A large, thick buildup of callus can eventually crack, with the cracks extending painfully into the living layers of your skin.
• Gymnasts and rowers know this one: a callus on your hand can rip off, exposing a raw wound underneath. If you’re grabbing bars or weights with your hands, you’ll want to keep that callus as thin and smooth as possible while still giving you some protection.

Calluses can also sneak up on you, so that you don’t notice you’re getting one until you’ve had it for a while. If a callus isn’t causing you problems, you don’t need to remove it.

You also don’t have to be paranoid about keeping them. If your calluses soften up in a post-race bubble bath, or if your pedicurist wants to smooth them down, you’ll probably be fine — just ask the pedicurist not to take off too much.

How to Tame Calluses on Your Hard-Working Hands and Feet

If you’ve decided that a callus is getting in your way, you have several options for taming it. In each of these cases, all you’re doing is removing those dead skin cells — the same ones you shed all the time. You’re just doing it faster than would normally happen. Here are some approaches to choose from:

• For everyday maintenance, soften your callus by taking a shower or bath, and then rub it with a washcloth or pumice stone to remove some of the softened skin.
• File the callus down with an emery board or a specialised foot file.
• Kick up the filing a notch with a microplane grater made especially for feet. Do not get this mixed up with the one you use for lemon zest.
• Use one of the many products in the bizarrely diverse callus filing industry, such as the PedEgg, which also comes in an electric version called the PedEgg Powerball. These are all just fancy files.
• Shave the callus (carefully!) with a specially made razor.

If you have a monster callus and these approaches aren’t quite enough, Dr Kupcha recommends salicylic acid preparations, sold under names like Dr Scholl’s Liquid Corn/Callus Remover. You put the solution onto your skin at night, put a piece of tape over it and then the skin will be soft enough in the morning to give you a better chance of removing the callus with one of the above methods.

If you get calluses all the time, and they bother you, it may be worth preventing them. For calluses on your feet, consider if you’re in the wrong size or style of running shoes, or if you need to fix the way you lace them to reduce pressure. Dr Kupcha notes that if you feel the need to add some padding to a place that is prone to blisters or calluses, put the padding around the painful area, not directly on top of it, or else you’re just adding to the problem.

We’ve mentioned several ideas that can help reduce the chance of blisters that are also good ideas for calluses (or if you’re getting that double whammy, a callus with a blister underneath). You can reduce friction by coating sore spots in bodyglide or gel deodorant. You can wear cut-off stockings under your socks. Or, following a recent study on ultramarathoners, you can use paper tape, cheaply available from pharmacies, on areas prone to hot spots.

For callus-prone hands, consider gloves. In some sports, like Crossfit, people argue against gloves, but not for especially good reasons. Know that there’s nothing wrong with using gloves, if you prefer them. Gloves, however, mean you have to consider whether your skin might now be rubbing against the glove instead of against the weight or pull-up bar. In that case, consider using lube or tape to reduce friction there. If a callus ever does rip, Dr Kupcha says to remove the flap that’s hanging off (nail trimmers will do the trick) and treat the open wound like an open wound. Keep it clean and covered until it heals.

How to maintain the optimal level of callus is something you’ll have to dial in over time, depending on your sport and perhaps on the fit of your shoes or gloves. Wield that callus razor carefully, and good luck.