What Is Hair Density?

You can categorize your hair in many ways — by its length, color, texture, coarseness, or density. Your hair density refers to how many strands of hair grow per square inch of your scalp.

Hair density is one factor that determines how to best style your hair.

It’s not necessary to get out a microscope and start counting individual strands. Just having a general idea about whether your hair density is on the thin or thick side can help you determine what type of hair products you should be using.

Let’s go over how you can figure out your hair density at home. We’ll also take a look at what types of cuts and products are most suitable for hair density type.

What’s typical hair density?

We typically have 80,000 to 120,000 hairs on our scalp. Your hair density is generally highest at your vertex, the area at the back of your head also known as your crown.

Hair density varies widely from person to person and tends to differ by ethnicity.

There’s no such thing as a hair density that’s too high or too low, and your hair density isn’t indicative of your overall health. However, people with nutritional deficiencies may experience hair loss that reduces overall hair density.

2017 study compared the hair density of people of Hispanic descent to those of African or Caucasian descent. The study found that people of African descent had the lowest hair density and Caucasians had the highest.

The researchers found the following hair densities at the crowns of the participants’ scalps:

Ethnicity

Hair density (hairs per square inch)

Caucasian

1,458

Hispanic

1,148

African

961

 

Another study looked at the typical hair density of Thai adults and found hair density also varied by age.

These researchers observed the following hair densities at the crown:

Age

Hair density (hairs per square inch)

20–29

1,064

30–39

1,057

40–49

1,047

50–59

1,020

60–69

1,004

 

Determining hair density:

The most accurate — but least practical — way to measure your hair density is by counting the individual strands in a 1-inch by 1-inch section of your scalp.

Researchers commonly use an imaging technique called trichoscopy in lab settings to achieve this.

The gold standard method of measuring hair density is with a phototrichogram, an imaging technique that allows researchers to measure hair density and the growth phase of each individual hair.

Measuring hair density at home:

A more practical way to get a general idea of your hair density at home is by a visual inspection.

If you can see your scalp without moving your hair, your hair density is likely on the lower end. If you need to move your hair slightly to see your scalp, your density is probably somewhere in the middle. If it’s difficult to see your scalp, your hair density is likely high.

Another test that’s popular online is the ponytail test. The test works by putting your hair in a ponytail and measuring the circumference.

You can guess your hair density based on how thick your ponytail is and comparing it to the following chart:

Ponytail circumference

Hair density

Less than 2 inches

Low

2–3 inches

Medium

4 inches

High

 

This test can give you a rough idea of your hair density, but the thickness of each of your individual hairs also plays a role in determining the thickness of your ponytail. Of course, it also only works if you have hair long enough to put in a ponytail.

If you’re still having trouble determining your hair density, you can try asking a stylist or hairdresser.

What your hair density means for the care of your hair:

Knowing your hair density can give you an idea of what type of hairstyles and hair products will work best for your hair type.

Keep in mind that your hair coarseness, length, and texture, as well as your individual style play a role, too.

Low-density:

If you have low hair density, you may want to avoid heavy products that weigh your hair down like heavy oils and conditioners.

Look for products that can add volume to your hair like volumizing shampoos, dry shampoo, and mousse.

Hairstyles that add more volume to your hair can help give your hair a thicker appearance. Many stylists recommend sticking to cuts with blunt lines and minimizing layers.

Medium density

If your hair density falls somewhere in the middle, you don’t need to do much to change the volume of your hair.

You can focus on products that help keep your hair healthy while experimenting with different hairstyles and products.

High-density

If you have a higher hair density, you may need heavier styling products like gels and butters to get your hair to stick and keep it under control. Serums and oils may help reduce frizz.

Hairstyles that remove excess bulk may work best for you. Layering can help give your hair an illusion of being thinner, and many stylists recommend avoiding blunt cuts.

Can you increase hair density?

Like many other aspects of hair — like its color and texture — hair density is determined by genetics. Your hair grows out of a part of your skin called a hair follicle. You can’t change the number of hair follicles you have.

Hair transplantation surgeries may help cover patchy areas of hair growth, but if you were born with low hair density, there’s currently no way to change that.

You can help maximize your hair density potential by eating a healthy diet.

Healthy diet:

If you have one or more nutritional deficiencies, you may experience hair loss or thinning of your hair. Making sure you’re eating a well-balanced diet with an adequate protein intake can help you prevent deficiencies that may affect hair growth.

Some nutrients that play a role in hair growth include:

FUT and FUE transplant:

Follicular unit transplant (FUT) and follicular unit extraction (FUE) surgery are two methods of hair transplantation.

Typically, follicles are taken from one part of your scalp and transplanted to areas of your scalp that are balding or have poor hair density.

During FUT surgery, a surgeon cuts a strip of skin, typically from the back of the scalp, and then removes individual follicles. During FUE, the surgeon removes individual follicles directly from the scalp.

Bottom Line:

Your hair density is the number of strands of hair growing out of each square-inch of your scalp.

You can estimate your hair density at home by examining your scalp or measuring the circumference of a ponytail. If you’re unsure what your hair density is, you can also try asking a stylist.

If you have a low hair density, you may want to stick to hair products and hairstyles that add volume. If your hair density is on the higher end, you may want to focus on reducing volume.

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Written by Daniel Yetman on October 27, 2020
Photo Credit: Freestocks

 

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