Why Is Some Hair Curly and Some Straight? The Science

It Starts at the Follicle

To better understand the differences between straight and curly hair, we need to take a look at what is inside your hair follicle. Follicles that are straight will result in straight hair fibers. Curved follicles (even a slight curve) and you’ll likely have curly hair.

Did you know that researchers believe that the shape of your hair happens during the development of the embryo?! They don’t know why this occurs, but those that have S shaped hair will have a follicle that has two bends in it. This type of shape is permanent and you will most likely have curly hair throughout your lifetime.

Genetics also come into play in the production of curly hair. If you have family members with curls, chances are you will as well. A protein known as trichohyalin is responsible for this.

Here’s a bit of trivia you can tell people: When a strand of hair is cross cut, it is very round but when curly hair is cross cut it will be more of an oval shape.

What Are Some Differences Between Straight Hair and Curly Hair?

Those with straight hair (or with a slight wave) tend to have more oil because the natural oils that your scalp produces have an easier time passing through the follicle’s shaft. Therefore, those of you with straight hair will want to shampoo more often to keep the oil to a minimum. Curly hair tends to be drier because it is harder for the oils in your scalp to make their way to your hair. You may actually need to add oil to your hair. It is best for you to use shampoos and conditioners that are all-natural. They won’t strip your hair of its natural oils. Of course seeing a hair professional is beneficial as they will suggest the right protocol for you!

The Most Important Difference

You must maintain a healthy regimen for your hair to remain healthy. Pay close attention to your scalp and your hair to see if you need to wash more often or less often. Do you need to add oils to your hair or do you need to keep the oil at bay?

Many with straight hair want curly and conversely, those with straight hair may want curly. You can achieve this with heating tools or using chemicals and other processes to create curls or straighten. It won’t change you’re your hair permanently. Eventually your new growth will still sprout the way Mother Nature intended.

The hair and follicles do undergo changes through your life. If you have curly hair now it will always remain curly. However, if you have straight hair, it is possible that, over time, your hair follicles will develop a few changes, including becoming a bit curlier over time.

Frequently asked questions