By Mike Kocsis | 10 minutes read | Last updated: September 29, 2023 Categories: Hair Hormone imbalance Testosterone
Medically Reviewed by Dr. George Touliatos
Hair loss, also called alopecia, is a condition that causes excessive hair shedding due to an interruption in the hair growth cycle. It can occur anywhere on the body, but scalp hair loss is the most common.
Millions of men and women experience hair loss in the world. It is caused by genetic and hormonal problems. Having high or low levels of androgenic hormones increases hair loss risk. Some genetic factors also play their role in this regard.
In this article, we will explore how your hormones impact hair growth and cause hair loss.
Dihydrotestosterone (DHT)
Dihydrotestosterone is a sex hormone produced in both men and women. It is mainly responsible for the development of male sex characteristics such as:
- Deepening of voice
- Increase in body and facial hair
- Body fat distribution
- Muscle growth
- Development of prostate and prostate glands (during foetal development)
An enzyme 5-alpha-reductase (5-AR) converts around 10% of the total testosterone into DHA in various tissues, including hair follicles, prostate glands, and the brain.
DHT is stronger than testosterone and can link to testosterone sites for longer durations. Once it becomes available in the bloodstream, it travels to hair follicles and attaches to their receptors, shrinking hair follicles and making them unable to support hair growth.
High levels of DHT are linked with many other health problems, such as:
- Prostate cancer
- Coronary heart disease
- Slow wound healing
Having too little DHT can also cause hair loss. Additionally, it delays the onset of puberty and the development of secondary sexual characteristics in men. It may cause the following effects:
- High risk of aggressive prostate cancer
- Risk of gynecomastia
- Poor fat distribution in the body
- Poor hair growth
Hair growth cycle
In order to understand hair loss and hormone connection, let’s first see how hair grows.
The hair growth cycle is divided into four main stages:
Anagen: It is the longest phase that lasts for 2 to 6 years. During this phase, your hair continues to grow, and follicles keep pushing them out. Around 90% of hairs that you have are in this phase.
Catagen: In this phase, hair follicles shrink, and hair separates itself from the surface of the follicle, yet it stays within the follicle. This phase lasts for around 2 weeks.
Telogen: It is the resting phase during which follicles become dormant for up to 4 months.
Exogen: It is an extension of the telogen phase. During this phase, hair is shed. It is normal to lose 50 to 100 hairs per day that are in the exogen phase.
How is DHT connected to balding?
Hair follicles are the openings on the skin surface that surround the root of the hair. Normally, hair within a follicle completes its growth cycle in 2 to 6 years before it falls out. When you shave your hair, the same hair comes out of the follicle as it still has its roots within the follicle.
Free DHT attaches to follicle receptors and begins a miniaturisation process, during which follicles shrink and stop growing new, healthy hair. Over time, your hairs become thin and brittle, and they start shedding faster. Follicles also start taking more time to grow new hair.
Soon, you will notice thin areas on your scalp. In most men, it begins at their hairline, causing a receding hairline that is the first sign of hair loss.
DHT and genetics
You might be thinking that all men produce DHT, but only some start losing hair at a young age, while others don’t experience this problem. Well, it is because of the difference in their genes.
People who have variations in their androgen receptor (AR) genes are more susceptible to hair loss. The androgen receptivity of their follicles increases, and they become more sensitive to DHT.
How to reduce DHT to control hair loss?
Doctors often prescribe DHA blockers or inhibitors to help people with DHA-related hair loss reduce the effect of DHA. Blockers prevent the attachment of DHA with receptors, and inhibitors reduce DHA production.
Finasteride is the most commonly prescribed oral medication. Finasteride binds to receptors to block DHA binding. Studies show it has an 87% success rate.
Hair loss in women
Women also experience this problem; however, it is not as common in them as it is in men. Their levels of testosterone and DHT are much lower than men, but still, the abundance or deficiency of these hormones can cause hair loss.
Hair loss patterns are different in women. They start losing hair from the top of the head, and their hairline mostly does not recede.
Other causes of hair loss
You can have hair loss due to many other reasons, such as:
Low testosterone levels
Low testosterone, or low T, occurs when gonads fail to produce enough testosterone. It can be congenital or acquired.
Testosterone deficiency affects social, mental, and physical health in various ways. People with low T start losing muscle mass and bone density with time. They may develop erectile dysfunction and have a low sperm count. Their facial and body hairs become thin and weak.
Low-T men should get timely treatment to reduce low-T effects. Testosterone replacement therapy (TRT) increases serum testosterone levels in low-T men. It is given in different forms, such as testosterone gels, patches, pellets, injections, and tablets.
Deficiency of thyroid hormones
Thyroid hormones regulate many important processes in the body. When your thyroid system does not produce enough hormones, your metabolism will likely slow down. Your hair growth will decline, and your body and facial hair will start falling out. The same happens when your thyroid glands become overactive.
Thyroid hormone deficiency produces many other effects, such as sluggishness, tiredness, and depression. If these symptoms are disturbing your life and you want to improve your life’s quality, you should reach out to a hormonal specialist and get your thyroid glands checked.
Deficiency of vitamin D
In addition to building bones, vitamin D plays many other important roles. It stimulates hair follicle growth and maintains the hair cycle. Studies show that women with female pattern hair loss may also have vitamin D deficiency.
People usually get vitamin D through sunlight exposure or vitamin D-rich foods. Doctors may also prescribe them vitamin D supplements if their levels are too low.
Lifestyle
Poor lifestyle habits can fluctuate your hormone levels and disturb your health in several ways. Your diet plays an important role in this regard. You should have a balanced diet consisting of a healthy proportion of essential nutrients, i.e. proteins, carbs, and fats.
Taking too little protein can disturb your hair growth cycle. Similarly, the lack of plant-based foods can cause vitamin and mineral deficiency, leading to hormonal problems. Processed foods having high trans-fat concentrations can reduce testosterone production. Excessive alcohol consumption also produces a similar effect.
Emotional habits can also disturb your endocrine system. You should try different stress management exercises to handle day-to-day stressful conditions better.
Lack of sleep is another contributing factor. Adults should sleep from 6 to 8 hours per day to give their bodies enough time to repair and produce essential hormones.
Certain medical conditions
Some diseases like cancer, high blood pressure, and gout may disturb hormone balance, leading to hair loss. Certain medications can also produce the same effect. However, this hair loss can be temporary and go away as your condition gets better or you stop taking medications.
Testosterone replacement therapy (TRT) and hair loss
Testosterone replacement therapy (TRT) is used to increase serum testosterone levels in men who cannot produce this hormone naturally. Although this treatment is beneficial, it may cause hair loss in some patients (particularly those who are genetically susceptible to hair loss).
If you experience hair loss after starting TRT, you should discuss this problem with your doctor. They will examine your hair health and testosterone effects to identify what exactly is causing the problem. They may readjust your testosterone dose or prescribe you some medications to prevent this uncommon side effect.
Like other medical procedures, TRT also produces some side effects. However, its benefits outweigh its side effects. That is why several men choose this treatment to boost their testosterone levels and improve their lives.
TRT helps low-T men in the following ways:
- Bones become harder, denser, and stronger.
- Lean muscle mass and muscle strength.
- Improves sexual function and may treat erectile dysfunction.
- Improves the function of the fat distribution system and may make it easier for people to lose weight.
Wrapping up
Hormones play various roles in the body. Fluctuations in their serum levels can cause serious consequences.
Testosterone and DHT are sex hormones that mainly control the development of sex characteristics. Having too much or too little of these hormones can contribute to hair loss in both men and women. That is why you should try to maintain hormonal balance.
If your hair loss is due to hormonal imbalance, you should get checked by a hormone specialist to start a suitable treatment and reverse the effects of the problem.
References/Bibliography/Further reading/Citations/Scientific studies
Yip, L., Rufaut, N. and Sinclair, R., 2011. Role of genetics and sex steroid hormones in male androgenetic alopecia and female pattern hair loss: an update of what we now know. Australasian Journal of Dermatology, 52(2), pp.81-88.
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