Why Does the Inside of Your Shoes Turn Black? (Black Shoe Gunk)

Shoes can do a lot of things for your feet. They can make your feet look sexy, match your outfit, and help keep your feet warm. They can also leave behind black and white residue on the inside – leaving you to ask yourself some important questions like: “what is this black gunk in my shoes?”, “Why does the inside of my shoes turn black?”, and “how do I remove dead skin from my shoes?”

Why Does the Inside of My Shoes Turn Black?

In order to understand why skin turns black in shoes, it helps to first understand why shoes turn black. Some shoes are made with a material called leather. Leather is produced from the skin of an animal and because animals have sweat glands, the skin of an animal can hold sweat.

Sweat absorbs dirt and oil that settles on a person’s feet and feet sweat a lot. Dirt sticks to shoe leather quite easily, creating a thin layer of dirt on the outside of your shoes. The inside of your shoe is usually made from cloth or some other material that does not absorb this oil and sweat as easily as leather.

This results in the oil and sweat being absorbed into the inside of the shoe which then causes it to turn black because it has nowhere else to go but onto your foot which has been perspiring all day long. This combination makes it look like you have been wearing dirty shoes for weeks even though you just bought them yesterday.

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So… The most common reason why the inside of your shoes turns black is due to a buildup of dirt and grime on the soles of your feet when you wear shoes barefoot.

The grime is most often generated by sweat and dead skin on your feet mingling with dirt, dust, or sand picked up during your travels; this can lead to discoloration in your shoe or sandal.

Additionally, if you wear dark socks, stockings, or anything else that is a dyed material, the sweat from your feet can cause this dye to rub off on the inside of your shoes.

What Is the Black Gunk in My Shoes?

Have you ever experienced this black, sticky, and smelly gunk on the inside of your shoes? This black, smelly, and stubborn gunk is dead skin. Dead skin is gross, but it’s something that happens to the bottoms of our feet every day.

Your feet are covered with a thick layer of skin which keeps your feet protected from germs and bacteria. The bottom of your feet is tough, durable, and can withstand things most other areas on your body cannot.

Because of this trait of the bottoms on your feet, dead skin will harden into thicker layers. These layers can build up over time causing that nasty goop to form.

Black residue in your shoes is perfectly normal. This is especially common in active footwear that people typically don’t wear socks with such as rock climbing shoes or certain foot racing shoes.

The black marks are simply the accumulation of dead skin cells, dirt, and bodily oils rubbing off of your body and onto your footwear.

This is incredibly common and is no cause for concern as long as you practice sensible hygiene and wash your shoes when they get too dirty.

Most people don’t notice this because they wear socks with most of their shoes, but athletic footwear is often used under sweaty, strenuous conditions that can make it more apparent to the athlete.

Why Do My Shoes Turn My Feet Black?

Wearing certain shoes often stains the bottoms of your feet for several reasons. Although your feet get stained by dirt in sandals, it’s more likely that dye in your shoes is the root of the problem.

Reasons for Shoes Staining Feet:

With leather shoes, sweaty feet lead to a wet shoe sole and cause the dye to leak out. This is what often stains your feet. The same thing can happen when wearing suede shoes.

Additionally, shoes may stain your feet because you aren’t wearing socks. With closed-toed shoes, wearing socks creates a barrier between shoe dyes and your skin.

How Do I Keep My Feet from Turning Black in My Shoes?

There are two super simple ways to keep your feet clean in your shoes so they don’t turn black; you can either use hairspray or Vaseline.

  1. Hairspray. Apply a generous amount of hairspray to the insides of your shoes, and let them dry for 24 hours before wearing.
  2. Vaseline. Use a cloth to apply a substantial amount of hairspray to the inside of your shoes. Allow it to sit for 24 hours, then wipe off any excess Vaseline before letting them dry again.

That’s it! Your feet will now be free from any black residue no matter how long you wear your shoes!

How Do You Remove Dead Skin from Shoes?

Dead foot skin and its bacteria often build up on the inside of shoes. This leads to foul odors and stains that can be hard to remove.

Getting Rid of Dead Skin

Luckily, you can remove dead skin and bacteria from shoes by scrubbing them. A few methods you might try include:

  • Scrubbing with a moist towelette or bath wipe
  • Scrubbing with a gentle baking soda solution.
  • Using a small brush like a toothbrush will get into the nooks and crannies of your shoes.
  • Finally, you can exfoliate and remove dead skin from your feet before even putting your shoes on.

In summary, the black stains on the insides of your shoes are usually caused by one of two things: either the dyeing process used to color leather shoes is incomplete, or it’s the result of some kind of chemical reaction between the dye and a substance in your shoe.

A poorly dyed pair of leather shoes can cause the dye to bleed out onto your feet, leaving a black residue that will be transferred back onto your socks and skin.

The same thing can happen if you wear rubber-soled shoes in water or on wet or damp surfaces. The rubber is porous, so it absorbs moisture and then transfers it back to wherever you’re stepping.

The “gunk” inside your shoe is actually a combination of several things: skin cells, sweat, and salt. Salt plays an important role in this process because it causes leather to turn black when it’s exposed to moisture. Salt acts as an agent that draws out more moisture from leather than it can absorb on its own.

When the salt mixes with sweat and skin cells, it forms a sort of paste that eventually becomes sticky. The end effect is similar to what would happen if you rubbed candle wax into your shoe. It’s disgusting, but fortunately, there are ways to clean up this mess once it’s happened to you.

You may also be interested in… Are Timberland Boots Worth It? and Do Shoes Go Bad Over Time?