Why Doesn’t My Hair Grow?

Throughout life, we get used to how our hair grows naturally. Our expectation of a certain speed of growth, fullness, and appearance comes from years of it happening at a predictable pace. When we experience a change in these patterns, it can feel disruptive, cause anxiety, and affect our self-esteem. 

You may have noticed a change in your hair growth patterns. You may have been looking for techniques to kickstart your hair growth. Or you may want to know why exactly you are experiencing these changes. 

Many factors come into play when it comes to slowed or no hair growth. Here are a few of the biggest ones.

Hair Cycle

Before we can understand the factors limiting hair growth, let’s review the source of hair development and its life cycle.

We are born with all the follicles on our bodies that we will ever have — around five million of total body hair, one million of which are on our scalp. These follicles comprise two parts, one residing in our skin and the hair shaft that grows out of it. 

Healthy hair follicles produce hair in a four-stage cycle:

1. Anagen Phase – The anagen phase is the active or growth phase of the hair cycle. During this phase, the follicle produces hair from the protein keratin. On our scalps, this phase lasts between two and six years.
   
2. Catagen Phase – During the catagen phase, hair growth slows. Our follicles begin to shrink during this phase, and the hair separates from it but does not fall out. The catagen phase typically lasts four to six weeks.
   
3. Telogen Phase – This phase is also known as the resting phase. Hair in the telogen phase is no longer growing but still hasn’t started to shed. This period lasts about three months.
   
4. Exogen Phase – The final phase of the hair cycle is when hair begins to fall out of its follicles. During this phase, which can last two to five months, you may notice more hair than usual shedding onto your pillow or while showering.

Genetics

Genetics is at the top of the list of many factors that affect hair growth. Have you ever noticed how certain families just seem to have full heads of hair, and others seem to be bald sooner? This is largely due to the genes they’ve inherited.

If you’re wondering why your hair is not growing like it used to, it is most likely due to hereditary factors. Male pattern and female pattern baldness, two major causes of hair loss, are both inherited. Even celebrities are not immune to hair loss, proving the condition can impact anyone.

Age

Although slowed hair growth can begin at any point in our lives, it becomes more common as we age. Some estimates suggest that men’s likelihood of hair loss and baldness increases 10 percent with each decade of life. 

In other words, by age 50, about 50 percent of men will experience significant hair loss or balding patterns; by age 60, about 60 percent will.

When it comes to age, there are other factors to consider. How you’ve treated your hair through its lifetime can cause changes in growth — specifically hairstyles that cause excess tension on the scalp and overexposure to chemicals from bleaching and dyeing.

Lifestyle

Although we cannot control the genes we have inherited, we do have some control over our lifestyle. If you’ve noticed your hair is not growing as it used to, you may want to take a deeper look at your overall health and lifestyle. 

Here are a few areas you can improve to encourage hair health.

Diet

Since elementary school, we have heard over and over the importance of a healthy diet from our families and teachers. You’re probably familiar with the expression, “you are what you eat.” Although you may be tired of hearing it, there is a lot of truth to this cliche.

Just as a proper diet gives our body the nutrients it needs to operate at peak performance, the same is true of our hair. Evidence shows that deficiencies of proteins, Vitamin B12 and D, iron, and riboflavin can contribute to slowed hair growth.

These foods can help you get those necessary nutrients:

• Eggs
• Avocadoes
• Berries
• Fatty fish – mackerel, salmon
• Nuts and seeds
• Red meat
• Sweet potatoes

In addition, a daily multivitamin can help you get vitamins, nutrients, and minerals that you cannot get easily from diet alone.

There is also evidence that poor diets of heavily processed foods, excess sugar, diet sodas, and junk food can all contribute to hair loss and slowed growth — so it can be smart to avoid these as much as possible.

Exercise

Although you don’t need to push your body to Olympic-level athleticism to encourage hair health, a sedentary lifestyle could determine why your hair won’t grow.

Exercise increases blood flow and circulation throughout the body, including the scalp, encouraging hair growth. A good place to start is following the CDC’s guidelines of 30 minutes of cardio and strength training five days a week.

Sleep

Getting enough sleep can be challenging as an adult, but it’s worth it, with benefits far beyond just putting us in a good mood for the workday. A lack of sleep can reduce our immune system response and compromise the healthy functioning of our bodies, potentially weakening the health of hair follicles. 

In the case of sustained sleep loss, people can suffer from telogen effluvium, a disorder that causes hair follicles to enter the shedding phase of the hair cycle quicker and experience shedding at two to three times the normal rate.

In other words, if you are concerned about your hair growth, writing a sleep schedule and sticking to it should be a priority.

Smoking and Alcohol Use

This may come as no surprise, but smoking and alcohol use can have major health effects — especially when consumed excessively. Smoking can cause damage to DNA cells in your body, including follicle cells. This may lead to slowed hair production or permanent damage to these cells.

Currently, there are no proven direct links between alcohol consumption and hair loss, but alcohol compromises other systems valuable to health. For instance, excessive drinking may inhibit our bodies’ absorption of nutrients and protein critical to hair health.

It’s especially important to limit these bad habits when recovering from hair transplant surgery when optimal circulation and nutrient delivery are key.

Stress

We all experience stress — from the workplace to childrearing to the general rhythms of life. But high stress can cause a ripple effect across our overall health, including hair growth.

Excess stress can cause hair growth to slow, but particularly stressful events, such as the loss of a family member, injury, or childbirth, can cause several hair disorders.

These include telogen effluvium, which can triple the speed of hair loss in the telogen phase, and alopecia areata, which can cause the body to attack healthy hair follicles.

Incorporating breathing exercises and meditation into an overall healthy lifestyle can help get stress levels manageable.

Hairstyles and Treatments

One factor that many don’t take into consideration when their hair stops growing is the different treatments and hairstyles they’ve had over the years.

Repeated bleaching and dyeing can cause damage to the hair follicles. This is noticeable in a change in the hair quality they produce. Overly processed hair grows back dryer, more susceptible to split ends, and without the same luster.

Over time, hairstyles like braids, cornrows, and other tight styles can lead to excess tension on the scalp and stop hair growth and, potentially, permanent hair loss.

Hormones

A hormonal imbalance can cause changes in hair growth. 

Among the top contributors are: 

1. Dihydrotestosterone (DHT) –  DHT is a byproduct of testosterone that can bind to hair follicles. Although sensitivity to the effects of DHT varies from person to person, this bond can affect the ability of follicles to support healthy hair, causing significantly reduced hair growth and follicle health.
   
2. Thyroid issues (hyper and hypothyroidism) – Both an overactive and underactive thyroid cause hormonal imbalances, contributing to hair loss 

Medical Factors

Various medical conditions can cause changes in typical hair growth patterns. It is well known that cancer patients undergoing chemotherapy experience significant hair loss during treatments. Autoimmune disorders such as lupus can also reduce hair growth. 

Some common prescription drugs, including lithium, amphetamines (Adderall, Ritalin), and beta-blockers, may contribute to hair loss.

Environmental Concerns

One of the lesser-known contributors to hair loss is exposure to pollutants. 

Smog and other pollutants in the air can enter the bloodstream and cause damage to follicles. Extended exposure to these conditions may cause symptoms similar to male pattern baldness.

Find and Treat the Cause of Hair Loss

It can be difficult to accept slowing hair growth and the onset of baldness. But most of us will experience some degree of hair loss throughout our lifetime.

It can be hard to avoid obsessing over the factors we cannot control. But focusing on making some lifestyle changes first may help you feel more in the driver’s seat when it comes to adjusting to and accepting a change in hair growth. In the meantime, team up with Jae Pak MD Medical to get professional guidance and move closer toward optimal hair health.

Sources:

Psychology of Hair Loss Patients and Importance of Counseling | NIH

Most Men Experience Hair Loss–But it Isn’t Inevitable | NYU Langone Health

Telogen Effluvium–A Review of the Science and Current Obstacles | ScienceDirect