How Long Does It Take For Hair To Grow Back?

Last Updated on July 18, 2023 By Emma W. Thomas

The rate at which hair grows back varies among individuals and depends on several factors, such as genetics, overall health, and hair care practices. On average, hair grows about half an inch (1.25 centimeters) per month. This means it could take approximately 6 months to a year to grow 3 to 6 inches (7.5 to 15 centimeters) of hair length. However, this timeline can vary, with some people experiencing faster or slower hair growth.

How Long Will Your Hair Take To Regrow?

Depending on the cause of hair loss and the individual, it takes different lengths for hair to grow back. This table summarizes the causes of hair loss and the period it takes to regrow.

Cause of hair loss	How long will it take for hair to grow back?
A haircut	One month (to grow ½-inch)
Chemotherapy	After 3-months of thinning (soft hair appears on the scalp)
Pattern baldness	It doesn’t grow back.
Hormonal imbalances	Immediately hormonal level goes back to the baseline. (average growth of 6-inches per year)
Dermatological pathologies	Immediately the hair loss causing condition is cured, it takes one week to start growing back (at ½-inch a month). But, sometimes, the loss is permanent.
Waxing	A couple of weeks
Shaving	Two weeks
Medical conditions	One to two weeks after successful treatment of the condition

Hair Loss Due To Shaving

For an average healthy person, it takes one month for hair to grow back ½-inch. This theory is according to research by the American Society of Dermatology. But, the growth rate is different depending on whether one is male or female. 

Post-Chemotherapy Loss

This type of hair loss is common in cancer patients due to treatment. The hair goes through thinning for about three months, after which some soft hair starts sprouting on the skin. Although the growth rate is low at first, it will get normal after a few months. The standard rate is 6 inches per year. 

Pattern Hair Loss (Pattern Baldness)

This hair loss is common, especially in men, due to physiological processes and usually begins after forty years. Since this is a permanent process, the hair does not grow back, but it can be delayed using FDA- an approved cure. 

The human hair roots or follicles get damaged during pattern baldness, and hair cannot regrow. 

Hair Loss Due To Hormonal Disturbances

Hormones such as progesterone, testosterone, and estrogen play a significant role in hair growth. For example, whenever there is a testosterone rush, most people experience physiological hair loss. After the hormonal levels balance, the hair starts to grow back at an average rate of 6 inches per annum. But, there may be variations depending on an individual’s age and the level of hormones. 

Hair Loss As A Result Of Waxing

During waxing, the visible hair is removed from your scalp, which does not affect the hair roots or follicles. It takes only a few weeks for the hair to sprout back. Waxing the scalp is believed to help hair regrow faster. 

Loss Due To Dermatological Pathologies

Dermatological problems such as scalp psoriasis, fungal infections, and alopecia are significant causes of hair thinning. These microorganisms attack the hair follicle on the scalp leading to hair loss. Once the pathologies heal after medications, the hair starts to regrow immediately, but there are chances it may fail to sprout again. 

In most cases, your hair starts to grow at an average rate of ½-inch every month, one week after you recover fully from the ailment. 

Growing Hair Back After Medical Conditions

Some medical conditions such as diabetes and thyroid disorder are also common causes of hair loss. But, after successful treatments of these conditions, your hair can grow back. While this growth will be prolonged initially, it regains the standard speed of growth within one or two weeks. 

Shaving

It is common to shave facial hair using a razor to reduce it. This method eliminates only the hair above the follicle without interfering with its ability to grow back. After shaving, it takes a fortnight for the hair to regrow at a rate of ½-inch per month. 

Nutritional Deficiency

Lack of enough nutrients such as iron and zinc could lead to hair thinning over time. To enhance hair sprouting after a deficiency, ensure that you take food rich in these nutrients. The hair may take a couple of months to grow back. 

How does hair grow?

The process of hair growth is a fascinating one that involves some complex processes. This article will provide an in-depth exploration of the essential factors that contribute to hair growth. 

1. Anatomical Structures of Hair: Hair emerges from follicles within the skin of a mammal. Primarily, there are two parts to a hair:
   • The Shaft: This is the visible part of the hair, extending out from the skin’s surface.
   • The Root: This is the portion beneath the skin, anchored into the hair follicle.
2. The Hair Growth Cycle: Each strand of hair follows its independent path throughout these three stages:
   • Anagen Phase: During this phase, the cells in the hair bulb actively divide and incorporate to form new hair growth.
   • Catagen Phase: Here, the hair stops growing. The outer root sheath shrinks and attaches to the root of the hair.
   • Telogen Phase: This is the resting period before the hair falls out. The follicle remains inactive for 1-4 months.
3. Nutrition and Hair Growth: Proper nutrition plays a significant part in promoting healthy hair growth and, conversely, multiple deficiencies can lead to hair loss. Some essential nutrients for hair growth include:
   • Protein: Hair is primarily made of protein, making adequate protein intake necessary for hair growth.
   • Vitamins: Such as B vitamins, vitamin D, and vitamin E.
   • Minerals: Including zinc, iron, and omega-3 fatty acids.

Nutrients	Importance
Protein	Primary component of hair
Vitamins	Promote cell growth and repair
Minerals	Strengthen Hair

4. Role of Hormones in Hair Growth: Hormones can influence the growth of hair in several ways. Some hormonal factors that affect hair growth include:
   • Androgens: These hormones, including testosterone, affect the hair growth cycle and can lead to conditions like male pattern baldness.
   • Estrogens: Higher estrogen levels may prolong the anagen phase, leading to longer, healthier hair.
   • Thyroid hormones: An imbalance in thyroid hormones can lead to hair loss or thinning hair.
5. Genetic Factors: Genetics also play a role in determining individual hair growth rates, the duration of growth cycles, and the onset of hair thinning or loss.

How Can You Support Your Hair To Grow Back?

Trying to grow your hair back after thinning could be pretty challenging. It is easier and more practical to prevent the loss by keeping your hair as healthy as possible. Some of the methods to maintain healthy hair include;

• Eating healthy food with enough vitamin C, proteins, iron, and zinc. Since hair is composed mainly of proteins, it is necessary to consume it to enhance growth. 
• Taking supplements such as folic acid, biotin, iron, omega-3, zinc, and omega-6 can also help maintain and grow healthy hair. But, one needs to consult a doctor to know if it is okay. 
• Avoid excessive heat and harsh chemicals on the scalp and hair
• Always massage your scalp after washing your hair to enhance blood circulation to the follicles. 
• Use hair products such as conditioners and shampoo with keratin or vitamin E. You could also consult a dermatologist if you have scalp psoriasis to get a prescription for a medicated shampoo. 
• You can get rid of split ends by trimming them every six to eight weeks.
• Avoid smoking
• Wear a hat regularly to protect your hair from exposure to excessive sun

What affects the regrowth of hair?

1. Nutritional DietA well-balanced diet plays a vital role in the regrowth of hair. Hair is composed of protein, so a diet rich in protein can contribute significantly to hair regrowth.
   • Foods such as fish, chicken, and eggs are good sources of protein.
   • Moreover, diets low in vitamin D, iron, and zinc may also slow down hair growth.
2. Hormonal ChangesFluctuating hormone levels can lead to hair loss or slower regrowth, especially in women.
   • Pregnant women often experience hair loss, but regrowth usually occurs after childbirth.
   • Menopausal women may also experience hair loss due to hormonal changes.
3. Stress LevelsEmotional or physical stress has a significant impact on hair growth.
   • Stress may trigger telogen effluvium, a type of temporary hair loss.
   • Regular exercise, adequate sleep, and avoiding caffeine and alcohol can help manage stress levels.
4. Medical ConditionsCertain illnesses and conditions can inhibit the ability of hair to regrow.
   • Conditions such as alopecia areata, thyroid disorders, and scalp infections can affect hair regrowth.
   • Treatment for these conditions often helps in restoring hair growth.
5. MedicationsSome medications or treatments, like chemotherapy, can lead to hair loss.
   • Once the treatment is completed, the hair usually grows back.
   • However, sometimes the hair may not regrow to its original state.
6. GeneticsGenetics play a significant role in determining hair growth and loss.
   • If members of your family have a history of baldness, you may also stand a chance of experiencing hair loss.
   • Unfortunately, there is no definitive solution for genetic hair loss, but there are treatments available that may slow the process.
7. Hair Care PracticesBasic care for hair, like regular washing and avoiding harsh hair products, can affect the hair’s growth.
   • Excessive heat styling and permanent coloring can damage the hair and slow down regrowth.
   • Using a gentle shampoo, or conditioner, and limiting the use of heat styling tools, can promote hair growth.
8. EnvironmentEnvironmental factors, such as pollution, climate, and water quality, can also affect hair regrowth.
   • Areas with high pollution levels may have a higher rate of hair loss.
   • Using a water filter to reduce the mineral content in water can help aid in hair regrowth.

Factors affecting hair regrowth	Details
Nutritional Diet	High protein and vitamins intake
Hormonal Changes	Pregnancy, menopause
Stress Levels	Emotional, physical stress
Medical Conditions	Alopecia areata, thyroid disorders
Medications	Chemotherapy
Genetics	Family history of baldness
Hair Care Practices	Regular washing, avoiding harsh products
Environment	Pollution, climate, water quality

Conclusion

It takes different durations for hair to grow back after thinning, depending on the cause. But it is possible to prevent the loss by observing proper practices such as eating a balanced diet and using hair products that contain vitamin E and keratin. You can also shield your hair from excessive heat from the sun by wearing a hat and massaging your scalp.

References:

https://www.healthline.com/health/how-long-does-it-take-for-hair-to-grow-back
https://www.equibotanics.com/blogs/news/how-long-does-it-take-for-hair-to-grow-back