How Long Does It Take for Hair to Grow Back?
Your hair is part of your identity. People see the hair on your head every time they look at you. Losing it can change the way you feel about yourself and affect how you think others perceive you. If you have thinning hair or lost your hair—whether due to a medical reason or you shaved it—you may wonder how fast hair grows back. The answer starts with some hair basics and frequently asked questions.
All the hairs on your body grow out of a follicle. You have about 5 million follicles all over your body. About 100,000 of them are on your head. The rest are on your face and body. At the bottom of the follicle is the hair root. It consists of living cells that grow to form the hair shaft. As the hair shaft grows, it passes an oil gland and eventually pokes out through the skin. The hair is dead at this point which is why it doesn’t hurt to get a haircut, but it can hurt a bit to pull out a hair by the root.
Hair growth takes place in three phases—anagen, catagen and telogen phases. The anagen phase is active hair growth. The catagen phase is a transitional phase. And the telogen phase is the resting phase—when you normally lose up to 100 hairs per day. About 8% of your hairs are in the telogen phase at any time.
The length of hair growth phases varies by body area. Scalp hair stays in the anagen phase for anywhere from 2 to 6 years. It grows at a rate of around 6 inches per year. It spends 2 to 3 weeks in the catagen phase and then about 100 days in the telogen phase.
Other types of body hair, such as eyebrows and leg hair, have a much shorter anagen phase—about 30 to 45 days. This is why they are shorter than scalp hairs. Conversely, they have a much longer telogen phase, which is why you don’t shed as many of them.
Chemotherapy—or chemo—damages rapidly dividing cells. This is how it kills cancer cells. It also accounts for some of the side effects, including hair loss. Not all chemo drugs cause loss. When hair loss occurs, it can affect the scalp hair and body hair. It can be complete, partial, or just thinning, and hair typically does grow back after chemo. How quickly this occurs varies from person to person and it depends on the body area.
Because scalp hair has the most growth, it tends to regrow first after chemo. You may notice a soft fuzz on your head within a couple of weeks after chemo ends. It can take a month or longer for more normal hair to appear. Hair on other areas, such as eyelashes and eyebrows, generally takes longer to regrow. Until the effects of chemo wear off completely, you may notice differences in texture and thickness.
The short answer—it depends. Hair thinning or loss has a variety of causes. Some are reversible and some are not. This means the earlier you seek treatment—usually from a dermatologist—the more likely it will be for treatments to work.
There are several types of treatments available for hair loss. The right one for you depends on the cause of your hair thinning or loss. Hair loss with an underlying cause, such as a thyroid disorder, autoimmune disorder or low ferritin level, usually responds to treatment.
One common treatment for men with male pattern hair loss is the drug finasteride (Propecia). It slows hair loss in 88% of men and results in hair regrowth in about 66% of men. For women with female pattern hair loss, the topical product minoxidil (Rogaine) is the only FDA-approved treatment. It results in moderate hair regrowth in about 20% of women. However, there are several other ‘off-label’ treatments doctors can use.
Your doctor or dermatologist is the best resource for hair loss treatments based on the underlying cause.
There are many myths about hair after shaving—it grows back faster, thicker or darker. The fact is shaving does nothing to the hair follicle, which is responsible for hair growth. Hair may appear thicker or darker after shaving, but it really isn’t. Normally, hair shafts have a tapered end. When you shave it, you create a blunt end which can make hair look darker or feel coarser.
Many people dealing with hair loss wonder how to make hair grow back faster. Even people without hair loss may search for ways to make hair grow faster. Lots of products may even promote or make claims about faster hair growth. The truth is there is no way to make your hair follicles grow hair faster. However, you can take steps to ensure your hair growth and condition is optimal:
Eat plenty of protein. The hair root depends on protein. If your body does not get enough protein, it will conserve protein by shutting down hair growth. Feed your hair roots by including meat, eggs, fish, beans and nuts in your diet.
Include iron. Iron deficiency can lead to hair loss. Good sources of iron include red meat, beans, lentils, fortified cereals, and green leafy vegetables, such as spinach.
Protect your hair when swimming. Wear a swim cap, rinse your hair right after swimming, and use a swimmer’s shampoo.
Treat your hair gently. Massage your scalp when you shampoo. Use conditioner every time you shampoo. Don’t rub wet hair with a towel to dry it. Use a wide-tooth comb on wet hair instead of a brush. Lower the heat on hair dryers and use hot styling tools sparingly. Avoid regular use of styles that pull your hair tight, such as buns or ponytails, and limit use of hair weaves or extensions.
If you are concerned about hair loss, see a dermatologist sooner rather than later. Early treatment offers the best chance of restoring healthy hair.