What Are Eyebrows For? Brow Facts You Never Knew

I’m obsessed with eyebrows—as a fact, that's been well-documented. I’m fascinated with testing the best products and finding the most natural-looking shape, that’s a given, but I’ve lately also found myself equally as interested in researching their history.

Why are brows so important to us? What are all the bizarre facts I never knew about my favorite accessory? Well, after a few too many 4 a.m. Google deep-dives, I have the answers. (Well, that, and the knowledge I gained after chatting with a couple of my favorite brow experts on the subject.)

Ahead, brow experts and makeup artists share some little-known facts about eyebrows.

01 of 10

Your Brows Can Have Cowlicks

Lily Collins wears bold eyebrows and a subtle pink makeup look — @lilyjcollins

“Oftentimes eyebrows have cowlicks just like we have on our head. This is more likely to happen if you have wavy or curly hair, although it can also happen on those with straight hair. This is especially important to know because when you are trimming the brows, you need to trim in the direction that the hairs are growing. When you isolate a cowlick, you must notice the wave pattern or the direction it's growing in and work accordingly.” —Tonya Crooks, celebrity brow expert

02 of 10

Your Brows Are More Active in the Summer

Zendaya wears bold eyebrows, dewy makeup, and box braids — @zendaya

Need another reason to take a warm-weather vacation? Here's one. “Your brow hairs grow faster in the summer because of the warm weather and the fact that we’re more active. In the winter, they slow down,” says Elke Von Freudenberg, a celebrity makeup artist and brow specialist.

03 of 10

Your Brows Give You Better Vision

Close-up of woman's face with brushed brow, banana clips, and minimal makeup — @glossier

The shape of your brow bone and the brows themselves keeps rain, moisture, and sweat away from your eyes so your vision stays clear. It's the reason you have eyebrows.

04 of 10

Brow Gel Wasn’t Always a Thing

“Brow gel is a recent thing. Today’s brows are a more groomed version (well-shaped and trimmed) of the thick, full brows from the ’80s. But back in the day, we used clear mascara to hold our brows thoughtfully in place. Today we have products that not only specifically are meant to hold the shape of the brow, but [are] waterproof to protect against sweat.” —Tonya Crooks

Brow gels aren't just reserved for your brows. They can also be used to tame stubborn baby hairs.

05 of 10

The Mona Lisa Doesn’t Have Eyebrows

Mona Lisa painting of woman smiling at artist by Leonardo da Vinci — Getty Images

If you already knew this or never thought about it, we don't blame you either way. Just think of all the tourists taking pictures with the painting and never once realizing Mona Lisa's famous face doesn’t include the feature we’ve come to love so dearly. But a 2007 CBS report suggests either Leonardo da Vinci revised the painting (removing the brows) or they had been unintentionally removed when the painting was cleaned.

06 of 10

Eyebrows Don't Actually Do Anything to Change Your Face or Eye Shape

Cara Delevingne wears bold eyebrows and a smoky eye — @caradelevingne

“What they do is give people an impression of you. Are you happy? Sleepy? Mad? Surprised? Your eyebrows give a very quick first impression of the type of person someone thinks you are.” —Elke Von Freudenberg

07 of 10

Strong Brows Are Not Just a Passing Trend

Woman wears full brows, lashes, and glossy lips — @benefitcosmetics

“Brows are no longer considered a trend but an industry focus, becoming a major category in makeup."—Jared Bailey, Benefit Cosmetics global brow authority. According to a Statista report, over 80 million women in the US used eyebrow pencils in 2020.

08 of 10

Unibrows Were Seen as a Sign of Intelligence

Many cultures throughout history held the unibrow in very high esteem. While we’re more apt to pluck or tweeze, many notable figures have exaggerated the hair because it was considered to portray intelligence and beauty.

09 of 10

Stress Affects the Growth of Your Eyebrows

Woman with bold, defined eyebrows, winged liner, and neutral lipstick — @benefitcosmetics

“Stress can cause your brows to grow slower or not at all. I see brides trying to get their brows growing for the big day, and then once the honeymoon is over, their brows finally are growing in.” —Elke Von Freudenberg

10 of 10

Your Hair Follicle Attempts to Recover the Hair After You’ve Plucked It

Hannah Bronfman wears brushed brows, mascara, and dewy skin — @kosas

“Does the skin around your eyebrow bump up right after you tweeze or wax? It’s usually the hair follicle closing to save the hair. It relaxes in about two hours and then it’s gone. It’s not a breakout. If you notice bumps two to three days after a tweeze or wax? That’s a breakout. That’s usually from a product that was applied right after the wax or tweeze,” Von Freudenberg claims.

How to Grow Thick Eyebrows

Article Sources

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American Academy of Ophthalmology. Why do humans have eyebrows and eyelashes? Updated March 23, 2017.
Statista. U.S. population: do you use eyebrow pencils? Updated July 2, 2021.
Jenkinson H. Consider the monobrow. JAMA Dermatol. 2017;153(7):659. doi:10.1001/jamadermatol.2017.1717