Androgenic alopecia is a form of hereditary or genetic hair loss that causes a degree of balding both in men and women. An estimated 80 million people are affected by androgenic alopecia in the United States alone (1). In this genetically predetermined condition, the genes can determine the onset of balding. The growth phase of hair slows down and the hair follicle shrinks, causing the follicles to miniaturize. This, in turn, produces shorter and finer hairs, leading to hair loss. Keep reading to understand the link between genetics and hair loss, its symptoms, and when you should see a doctor.

Genetic Hair Loss: What Science Says

Hair loss is distressing to deal with. You may have heard that if one of your parents or grandparents is bald, then there is a chance that you may go bald too. But, is it true? If it is true, then what is the link between heredity and hair loss? Let’s check out the scientific proof.

You can observe hereditary hair loss in both men and women, which are known as male pattern baldness and female pattern baldness. Hair loss tendency on both sides of the family is responsible for genetic hair loss, and it accounts for nearly 80% of this condition (2).

• Male Pattern Baldness

Male pattern baldness (MPB) often starts at the age of 20 or 30 as an M-shaped recession of the hair at the front of the scalp. Male pattern baldness affects 80% of men by the age of 80 (3). How quickly or slowly baldness develops is determined by the genes that you inherit from your parents. A study conducted at the Wright State University School of Medicine (USA) found that the probability of hair loss in males is dependent on family history and age (4). Though the genetic component responsible for male pattern baldness is not well understood, it is believed that it involves more than one gene (5).

Humans have 23 pairs of chromosomes in which all the genetic information is stored. One of these sets of chromosomes are comprised of X and Y chromosomes, which determine your gender. Babies inherit characteristics from their parents through these chromosomes. Baldness is closely associated with the androgen receptor (AR) gene found on the X chromosome (4). Men inherit this X chromosome from their mother (6). Men with AR genes have been found to have a tendency to develop male pattern baldness more than people without it (7).

Fact: It is estimated that humans have between 20,000 to 25,000 genes in their bodies (8).

Are only AR genes responsible for genetic hair loss out of the thousands of genes in the human body? No, research has also found that along with the AR gene, 63 more genes may play a key role in male pattern baldness (9). However, more research is required to understand male pattern baldness and the genes responsible for it.

• Female Pattern Baldness

In females, hair loss is gradual, and it can occur after the menopause stage, but some women may experience it sooner. Approximately 40% of women experience hair loss by the age of 50 and 55% of women by the age of 80 (10). When compared with male pattern baldness, female pattern hair loss may be less obvious as it presents in a different way to men. The gene responsible for this still remains unknown (11). It is believed that, like MPB, it also involves multiple genes. Generally, at least a quarter of all women experience some degree of hair thinning by the age of 50. Also, you can observe finer hair with less color at this stage.

Along with hair loss, you can also inherit sensitivity to one of the male sex hormones, DHT (dihydrotestosterone). DHT causes your hair follicles to shrink, which then leads to baldness (12). At puberty, testosterone starts circulating in the body if you are genetically predisposed to testosterone sensitivity. Unfortunately, this pattern is set. Testosterone binds to the AR receptor in the follicle with an enzyme called 5-alpha reductase (5AR). This converts the testosterone into the more potent dihydrotestosterone. This results in the follicles becoming miniaturized, creating shorter and finer hairs with each successive shortened anagen phase.

You may notice progressive hair thinning or balding in hereditary hair loss. But, is it the same in both males and females? Find out more in the following section.

Symptoms Of Genetic Hair Loss

In males, you can observe progressive thinning of hair, which starts with a receding hairline. This condition then leads to a bald spot at the crown area of your head. In the advanced stages of hair thinning, you may notice a rim of hair along the back of the head.

In females, you rarely observe bald patches. But, you may notice thinning of hair at the top of the head. For women, the temples and forehead areas are not usually affected. Most women report a widening of their parting, which shows more scalp.

You may observe thinning of hair as you age. But, if you notice it early in your life due to hereditary factors, can you reverse it? Find out in the next section.

Can You Reverse Genetic Hair Loss?

You cannot cure genetic hair loss. But, there are some options to slow down hair loss. Certain medications are prescribed by doctors to slow hair thinning, and you have to be extremely disciplined when taking them. These medications include:

1. Minoxidil: Minoxidil is an over-the-counter medication for hair thinning. It is more effective at the early stages of hair loss (13), (14). It is also known as Rogaine, and you should apply it twice a day to your scalp. It enhances the blood circulation in the affected area of the scalp and strengthens the hair follicles. It can be used by both men and women, but higher concentrations work best for men. Also, once this treatment starts, it needs to be continued for at least six months.

2. Finasteride: Finasteride is a prescription-only pill for hereditary hair loss treatment. This FDA-approved pill works by preventing testosterone from getting converted into DHT (a hormone that shrinks hair follicles) (15), (16). You need to take this pill once daily for at least six months. Also, it is only recommended for men.

Though genetic hair loss is normal, you should consult your doctor in case of sudden hair loss. Find out why in the next section.

When Should You See A Doctor?

Hereditary or genetic hair loss is natural. But, there could also be an underlying health condition causing your hair loss. If you observe sudden and patchy hair loss, scarring, flaking, redness, or hair falling out more than normal before your 30s, then you should consult a doctor.

There are few popular myths about baldness and hereditary hair loss. Learn more about them in the next section.

Myths Associated With Genetic Hair Loss

Myth 1: Genetic Hair Loss Only Happens To Men

It is estimated that nearly 30 million women in the United States alone experience female pattern baldness (1). They also experience more hair thinning, usually at the parting. The hair loss in women just presents differently from men.

Myth 2: Physical Activities Like Weight Training Cause Baldness

Although many studies do prove that physical activities enhance testosterone levels, there is no direct evidence that confirms a link between exercise and hair loss. It is believed that men with high testosterone levels have higher chances of male pattern baldness. However, it is important that this hair loss only occurs in men and women who are predisposed to testosterone sensitivity.

Myth 3: Baldness Is Caused By Sleep Deprivation, Stress, or Styling Options

Stress, super-tight hairstyles, and sleep deprivation can cause hair loss, but it is totally different from genetic hair loss. However, the link between these factors and hair loss are not well established.

Conclusion

Frequently Asked Questions

Is hair loss completely genetic?

No. Stress, nutrition, lifestyle, underlying medical conditions, and environmental factors can also trigger hair loss.

At what age does genetic hair loss start?

Genetic hair loss generally begins around the late 20s or early 30s.

Is hair loss genetic from mother or father?

Yes. Hair loss can be genetic and passed down from either parent (17).

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