We all have bad hair days, but a bad haircut can lead to bad hair weeks or months. Unless you go buy a wig or collection of hats, your hair’s rate of growth determines when you can get a new style. On the other hand, if your hair is colored, the rate decides when you will need to cover those roots. Instead of checking the mirror each morning, rest assured that most human hair grows at an average rate.
Human hair grows about a quarter to half an inch per month. At this rate, hair tends to grow about 6 inches or 12 centimeters per year. This varies from person to person, though. If you want to know for sure, measure a portion of your hair from month to month and average the result. If you have a bad haircut, the good news is that women’s hair generally grows faster than men’s.
A Saint Xavier University biology 101 class online resource explains that human hairs grow at different rates per month. Hair on the scalp grows half an inch per month. Hair on the face or other body parts tends to grow about one quarter inch per month.
Hairs live on your scalp for two to six years before they fall out, making room for a new hair–unless, of course, that life is cut short by being plucked, a punishment for its grey pigment. Each hair grows on your head about half an inch per month, or 6 inches per year, for up to six years. It then rests for a few months, not growing at all, before falling out.
If you are obsessing over the millimeters your hair grows each day, you may be interested to know that your hair has energetic moments throughout the day and takes breaks at other times. According to the Saint Xavier biology class preparation, your hair takes a cue from the rest of your body during the night and rests, slowing down its growth. It gets a energy boost in the late morning, from 10 to 11, as well as the late afternoon, from 4 to 6.
In a Yale dermatology document called “Hair,” David Leffell, M.D., explains that the common adage about shaving is false. Shaving a hair does not cause it to grow faster. You may infer this as smooth skin turns prickly faster than you would like. However, hair will grow at its normal rate, unless you undergo nutrition or hormonal changes.
- hair image by Dubravko Grakalic from Fotolia.com