When you think about it, fingernails are kind of incredible. Not only can they help you do things like play the guitar and scratch itches, but they can be painted and designed as a fashion accessory.

But have you ever wondered exactly how fingernails work, including why we have them and how they grow? In this post, you’ll learn all of these important basics.

Why do we have fingernails?

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Fingernails serve as one of our calling cards as primates.

It’s suspected that primates evolved from having more claw-like hand formations to hands with nails as a means of improving movement and locomotion. Our fingers and nails help us grasp, which is super handy for all sorts of activities like climbing trees or operating tools. They can also help protect us from danger!

The parts of the fingernail

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To understand what makes fingernails grow, it’s handy to understand the different parts of the fingernail. Here are some of the key parts:

  • Matrix: Just as hairs have a root, so does your nail, and it’s called the matrix. The matrix  constantly makes new cells under the skin, which later emerge as fingernail tissue. Ever wonder why it doesn’t hurt to cut your nails? By the time these cells begin to poke out of this pocket, they’re already dead, so they don’t cause you pain when they’re trimmed. The part of the matrix that you can see is the lunula (pronounced “loon-yoo-luh”), which is the half-moon shape at the bottom of the nail. Some people can visibly see it on all fingers, some can only see it on the thumbs, and on some people it’s not visible at all.
  • Cuticle: While manicurists are quick to cut or move the cuticles to the side, this tiny sliver of skin has a specific role in the health of your nails. It acts as a protective shield for the matrix, preventing germs from getting in.
  • Nail plate: This is what most people would call the fingernail. Made from translucent keratin, it appears pink because of the color of the blood vessels beneath. The texture of the nail isn’t exactly smooth. When you look up close, it has tiny grooves. This texture helps keep the nail plate in place.

What makes fingernails grow?

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What makes the fingernails grow? Rapidly dividing cells. The matrix or root of a fingernail is constantly generating new cells. As they grow, they begin to emerge from the little pocket-like sliver that acts as the bottom of your nail.

The rate at which nails grow will vary from person to person and may even vary from nail to nail. For instance, you may have noticed that your fingernails grow faster than your toenails. This could be due to increased use and circulation coming to the hands.

Additionally, you may notice that the nails grow faster on your dominant hand. It’s also possible that if you have a nervous tic of rubbing a finger, the nail on that finger may grow at a faster rate due to increased blood flow to the area.

Oh, and here’s a fun fact: fingernails are also said to grow faster during the summer.