How fast does hair actually grow? What dermatologists want you to know
So you want to know how fast hair grows. Maybe your barber was a little too liberal with the scissors. Maybe you've been dealing with some hair loss. Or maybe you want long, flowing locks but don't have the budget for high-end extensions.
Regardless of why you're interested in hair growth techniques, we're here to answer those FAQs. Board-certified dermatologist Dr. Hadley King tells Paste BN all about the truths (and falsehoods) regarding hair growth.
How fast does hair grow?
The average person's hair grows about half an inch per month or 6 inches per year, according to King and the American Academy of Dermatology Association (AAD).
The hair growth cycle consists of three stages: anagen (the growth period), catagen (the transition period) and telogen (the rest period). The anagen phase lasts about three to five years, King says. This is the time in which that particular hair will grow, and it can average anywhere from 18 to 30 inches total in its lifetime.
The catagen phase is much shorter – about 10 days – before the final telogen phase: "a resting phase when strands are released and fall out."
"It's normal to shed between 50 and 100 hairs per day," King adds. Once that cycle is complete, the hair follicle remains active for about three months before repeating the process all over again.
Is it possible to speed up hair growth?
While there are treatments to help promote better hair growth, they usually don't help to get you from a buzzcut to a throwback Justin Bieber flow overnight.
"Hair growth treatments generally work by keeping hair in the anagen phase longer, not by increasing the speed of hair growth," King explains. Sometimes people experiencing severe emotional stress, poor nutrition, significant weight loss, surgery, childbirth or a high fever caused by illness can develop a condition called telogen effluvium, which causes hair to spend less time in the anagen phase and appear thinner.
Anagen effluvium, a similar condition that causes hair loss due to hair follicles being injured during the anagen phase, commonly occurs during chemotherapy. It usually reverses once chemo treatments are over.
Rogaine is a popular treatment to help with some early hair loss, though the AAD notes it cannot regrow a full head of hair. There are also other medications available. Microneedling and laser caps or combs have also shown some early promising signs of being helpful, though the AAD stresses that more research is needed to confirm.
If you're experiencing hair loss, experts say the first step to figure out why that's happening.
When it comes to men, androgenetic alopecia (male or female pattern baldness) is to blame for about 95% of hair loss cases, according to NYU Langone. That probability drops down to about 40% for women. Other common causes can include genetics, hormonal imbalances, stress, medications, medical conditions or a vitamin deficiency. The course of action to remedy hair loss depends on the cause, which is why health experts stress meeting with a qualified medical professional before trying any treatments at home.
While there's a common belief that trimming your hair makes it grow faster, King says this isn't actually the case. But that doesn't mean getting a haircut every few months isn't still a good idea.
"Trimming helps to keep the hair healthy by removing damaged ends," she says. "This can help to decrease breakage, but it doesn't change the speed of hair growth."