Hair Density: What It Is, Why It Matters & How You Can ID Yours
When it comes to our hair, we hear a lot about color, cut, porosity, type, and length. But one factor that's commonly overlooked is hair density. And if we're being completely honest, that's probably because most of us have no idea what hair density actually is. Don't worry; you're not alone.
Though often misunderstood, hair density is actually important. There's high hair density, medium hair density, and low hair density. And the truth is, it affects the way we care for and style our hair—and gives us a deeper look into the appearance of our locks.
To help solve the mystery, we talked to hair experts to get the scoop on hair density, what it is, and why it matters. Keep reading to learn more.
What is hair density?
Hair density is often confused with the thickness or thinness of the strand. But the truth is, hair density refers to the number of strands on your scalp, according to celebrity hairstylist Ryan Richman. "The density of the hair is determined by how close your hair strands are to each other," Richman says. "This, in turn, determines how thin or thick your hair appears."
Professional hairstylist Sophia Porter explains that hair density is found by the number of hair follicles per every square inch of the scalp. So even though your hair may appear thin or thick, it doesn't necessarily correlate with the density of your hair. Yes, you can have high hair density and very thin or fine hair, and it's also possible to have thick, full hair with low density (more on this later).
What is average hair density?
One study found that the average number of hairs on the scalp can range from 80,000 to 120,0001, though this can vary for various reasons, including age, hair type, and perhaps even nutritional deficiencies. And before we begin, there's no density that's ideal—it's just a fact of hair that is individual to each of us.
One study found that age likely plays a role, with participants' hair density decreasing2 as they got older. This makes sense, as people often experience "thinning" with age—which is actually lessening density.
Certified trichologist and founder of Advanced Trichology William Gauntiz, WTS, says that the average hair density is based on genetics, but there are patterns among different hair colors. "Blondes typically have the greatest volume of individual strands per scalp at approximately 140,000 hairs," he says. "Brunettes have approximately 120,000 hairs on average, and redheads have the least amount of density with around 90,000 hairs."
How is hair density measured?
To no surprise, there are a variety of ways you can measure hair density. For starters, if you're making a visit to your local trichologist, Gauntiz says a microscope can be used to analyze the scalp and determine how many hairs are growing per hair follicle and per square centimeter. "Individuals can grow between one and six hairs per follicle," Gauntiz says. "Those producing one to two hairs per follicle would be considered low density, three to four would be average, and five to six per would be high."
If you're looking for a hair density test you can do at home, Porter suggests taking a front section of your hair and pulling it to the side. "If your scalp is very visible, you have low density, but if you can barely see the scalp, you have high density," she says. "If you're anywhere in between, that's medium density." It's also important to note that different areas of the scalp can have different densities. So, don't be alarmed if one area of your hair seems denser than others. According to the pros, that's totally normal.
You can also try the ponytail test if your hair is long enough:
- Ponytail circumference is less than 2 inches: Low density
- Ponytail circumference is 2 to 4 inches: Medium density
- Ponytail circumference is more than 4 inches: High density
How does hair density influence hair care?
Surprisingly, hair density does affect how we should style and take care of our hair. It's one of those factors that is easily overlooked or forgotten.
Low hair density
If you have low hair density, you should avoid oil-based products that will weigh down the hair and, "ultimately decrease the appearance of density," Gauntiz says. "Products like leave-in conditioners, heavy dry shampoos, and oil-based scalp treatments should be avoided when you have low hair density."
Not only does density influence the types of products you should use, but it also can make a world of difference in how you style or cut your hair. "Lower density hair should choose a cut that has blunt, heavy lines," says Richman. "A blunt bang or a heavy curtain bang can make the hair appear thicker.
High hair density
If you have higher-density strands, you opt for thicker, richer products, Porter suggests. "Variables like porosity and curl type will also play a large role in what is necessary to use." If you're not sure where to start, it's always best to consult a trichologist or hairstylist for suggestions that are best for your hair type.
For those with high density, choose a cut with more texture and layers to help remove weight from the hair. But Porter warns that it's important to find a stylist that specializes in thinning the hair to avoid damage and having bulky roots with thin ends. And since that's not exactly the trendy style you're looking to achieve, we suggest avoiding a DIY cut in this case. Your best bet is to leave this up to the pros.
Is it possible to increase hair density?
While you can't necessarily add hair strands to each of your hair follicles (that's all up to your genetics), there are ways to increase the appearance of denser hair. Enter, volumizing and thickening products. Think texturizing sprays, volumizing mousses, thickening sprays, shampoos, and dry shampoo. A few pumps or spritzes paired with a hair flip or two can give your strands major va-va-volume.
How can you improve hair density?
Since density boils down to your DNA, the only change that can occur is if there is damage to the follicle. If you think your lack of hair density is due to follicle damage, it's best to visit your local trichologist to get a proper assessment. Reversing follicle damage is very difficult—and perhaps impossible in some cases—so you'll need professional help.
Lessening hair density in some cases can be traced back to nutrition. If you fear that yours may be connected to any nutritional deficiency, visit your doctor to get your levels tested. Here are common nutrients that may be connected:
The bottom line.
As much as we'd like to control the density of our strands, the truth is, we can't. But if you're looking to make your hair appear denser, there's certainly a product that can help with that. But all in all, learning what type of hair density you have will help you learn how to style, cut, and care for your hair properly. And who would forgo a few more good hair days?
Andrea Jordan is a beauty and lifestyle freelance writer covering topics from hair and skincare to family and home. She received her bachelor's in Magazine Journalism from Temple University and you can find her work at top publications like InStyle, PopSugar, StyleCaster, Business Insider, PureWow and OprahMag. When she's not writing, you can find Andrea tackling new recipes in the kitchen or babysitting one of her many nieces and nephews. She currently resides in New Jersey with her husband and cat, Silas.