The most oft-quoted average rate of human hair growth is 6 inches (15 centimeters) per year. However, the majority of studies measuring the rate of hair growth didn't take into account the race of study participants.
Category
🤖
TechTranscript
00:00 How fast does hair grow?
00:03 If you get a bad haircut, it's reassuring to know that your hair will probably grow back soon.
00:09 But how soon? How fast does hair grow?
00:12 The off-quoted statistic is that human hair grows 6 inches a year.
00:16 However, when you take a person's racial background into account, you might see some differences.
00:21 According to a 2005 study on more than 500 people, Asian hair grows the fastest, about 6 inches a year.
00:28 The second is Caucasian hair, which grows a little more than 5 inches a year.
00:33 Next, African hair grows about 4 inches a year.
00:36 Also, it doesn't matter if you're a man or a woman.
00:40 Hair growth rate is fairly similar for both males and females.
00:44 There's also this nugget.
00:45 Some experts think that hair grows more quickly in the summer because of dietary changes.
00:51 That is, people are eating more fruits and vegetables.
00:54 During the summer, people can also experience hormone changes and get increased exposure to ultraviolet radiation from the sun.
01:02 But any seasonal increase in hair growth would be so marginal, it would be hard to notice.
01:08 How fast does hair grow? Just another one of life's little mysteries.