Can You Go Bald from Testosterone Therapy? What Studies Reveal About TRT and DHT

Introduction: The Growing Use of Testosterone Therapy and Its Hair-Related Concerns

Testosterone is one of the most important hormones in the human body. It plays a central role in developing male features such as deeper voice, muscle mass, and facial hair. It also supports bone strength, mood, energy levels, and sexual health. As men age, testosterone levels often decline gradually. For some, this drop can lead to symptoms such as fatigue, low libido, depressed mood, loss of strength, or difficulty concentrating. When these symptoms become severe, doctors may recommend Testosterone Replacement Therapy, commonly called TRT.

In the past two decades, the use of TRT has grown rapidly. Many men start therapy hoping to regain energy, improve sexual function, or rebuild muscle. Clinics advertise it as a way to “restore vitality” or “feel young again.” According to medical surveys, prescriptions for testosterone have increased several times over since the early 2000s. While this treatment can bring real benefits for those with medically low testosterone, it also raises many questions about side effects. One of the most common concerns men express before starting TRT is hair loss — specifically, the fear of going bald.

This concern is not unfounded. Hair loss in men is closely linked to androgens, the family of hormones that includes testosterone and its more potent form, dihydrotestosterone (DHT). People often hear that “DHT causes baldness,” and since testosterone therapy can raise DHT levels, they worry that TRT will make their hair fall out faster. Online forums and search engines are filled with questions like “Can testosterone therapy make you go bald?” or “Will TRT cause hair loss?” These concerns have become so common that hair loss is now one of the first side effects patients ask about during consultations for hormone therapy.

However, the link between testosterone therapy and baldness is not as simple as it may seem. To understand it clearly, it helps to look at how testosterone and DHT work in the body. Testosterone on its own does not usually cause hair loss. The issue arises when testosterone is converted into DHT through an enzyme called 5-alpha-reductase. DHT binds to receptors in certain hair follicles, especially those on the scalp’s crown and front area. In genetically sensitive individuals, this process can shrink the follicles over time, leading to thinner and shorter hair. Eventually, these follicles may stop producing visible hair altogether, resulting in what we call male pattern baldness.

Because TRT increases the amount of testosterone in the bloodstream, it can also lead to a mild rise in DHT levels. For some men who are genetically prone to baldness, this can mean that hair loss becomes more noticeable after starting therapy. Others may not see any change at all. Genetics plays a major role — if you have close relatives who experienced pattern baldness, your follicles are more likely to be sensitive to DHT. Without this genetic factor, even higher hormone levels might not cause visible hair loss.

Despite these facts, confusion remains. Some people assume that testosterone therapy creates baldness, but research shows it is more accurate to say that TRT may accelerate hair loss in those who are already predisposed. In other words, TRT does not cause baldness out of nowhere; it can simply make an existing tendency appear sooner. This difference is important for patients to understand when making treatment decisions.

The topic of testosterone therapy and hair loss also highlights how hormones interact in complex ways. For example, the body maintains a balance between testosterone, DHT, and estrogen. Changing one hormone through medication can influence others. Understanding these relationships helps doctors adjust TRT doses safely to support health without unwanted effects.

As testosterone therapy becomes more common, it is essential to separate myths from science. While some men worry about losing their hair, others may not notice any change or might even experience improvement in scalp health if hormone levels were extremely low to begin with. The truth depends on many factors — genetics, age, dosage, and the body’s natural hormone responses.

This article will explore what current medical studies reveal about TRT and baldness. It will explain how testosterone and DHT work, what scientific research shows about their link to hair loss, and how genetics influences the outcome. By the end, readers will have a clear, evidence-based understanding of whether testosterone therapy truly causes baldness or simply interacts with a person’s existing biological makeup.

The goal is to help readers make informed decisions about their health. Understanding how hormones affect the scalp and hair follicles can reduce fear and prevent misinformation. Testosterone therapy can be life-changing for men with low hormone levels, but it should always be guided by medical advice and awareness of potential side effects — including those that may affect the hairline.

In short, while the question “Can you go bald from testosterone therapy?” is common, the answer is not a simple yes or no. It depends on the individual. This article will examine the mechanisms, research evidence, and key findings that explain why TRT may influence hair loss in some people — and why others have no issue at all.

Understanding Testosterone and Its Biological Role

Testosterone is one of the most important hormones in the human body. It belongs to a group of hormones called androgens, which are responsible for male traits and reproductive function. While women also produce testosterone, men make much higher amounts, mostly in the testes. In both men and women, a small amount also comes from the adrenal glands, which sit on top of the kidneys.

What Testosterone Does in the Body

Testosterone has many effects that go far beyond reproduction. It acts on almost every organ and tissue. During puberty, testosterone helps boys develop deeper voices, facial and body hair, and increased muscle mass. It also supports the growth of bones and the development of sexual organs.

In adults, testosterone continues to play a major role in maintaining:

• Muscle strength and mass – It supports protein building in muscles, helping maintain physical strength.

• Bone density – Testosterone keeps bones strong by helping bone-forming cells stay active.

• Mood and energy levels – Low testosterone is linked to fatigue, low motivation, and irritability.

• Sex drive and erectile function – It fuels libido and supports normal sexual health.

• Cognitive function – Some studies suggest it helps with concentration and spatial reasoning.

Even small changes in testosterone levels can affect how people feel and function day to day.

How Testosterone Levels Change with Age

Testosterone levels are highest during the late teenage years and early adulthood. Around the age of 30, levels begin to decline gradually—usually by about 1% per year. This decline is a normal part of aging, but in some people, testosterone levels drop more sharply than expected.

When testosterone levels fall below a healthy range, doctors may diagnose a condition called hypogonadism. Symptoms of low testosterone can include:

• Low sex drive

• Tiredness or lack of energy

• Loss of muscle mass or strength

• Weight gain, especially around the abdomen

• Depression or mood swings

• Difficulty concentrating

• Thinning of bones (osteopenia or osteoporosis)

These symptoms often lead men to seek Testosterone Replacement Therapy (TRT) to restore hormone balance.

Endogenous vs. Exogenous Testosterone

It’s important to understand the difference between endogenous and exogenous testosterone.

• Endogenous testosterone means the testosterone your body makes naturally. It’s produced mainly in the testes under control of the hypothalamus and pituitary gland, which form part of the brain’s hormone control system. When testosterone levels are low, the brain releases hormones (LH and FSH) that tell the testes to make more.

• Exogenous testosterone means testosterone that comes from outside the body — for example, through a prescription therapy like injections, gels, patches, or pellets. These treatments are designed to raise testosterone levels in people whose bodies don’t produce enough naturally.

When someone starts TRT, the body senses the higher testosterone and slows down or even stops natural production. This feedback loop is normal, but it’s one reason why medical supervision is essential — to keep hormone levels balanced and avoid side effects.

How Testosterone Replacement Therapy (TRT) Changes Hormone Balance

TRT raises testosterone levels in the blood, which can improve energy, mood, muscle strength, and libido. However, increasing testosterone can also affect other hormones.

One key pathway involves an enzyme called 5-alpha-reductase. This enzyme converts a portion of testosterone into a stronger hormone called dihydrotestosterone (DHT). DHT plays an important role in male sexual development and the growth of facial and body hair — but it is also the hormone linked most closely with male pattern baldness.

TRT can also increase levels of estradiol, a form of estrogen. Some testosterone in the body is converted to estradiol through another enzyme called aromatase. This process helps balance hormones but can also cause side effects, such as breast tissue tenderness or water retention, if levels rise too high.

Different Forms of Testosterone Therapy

Doctors can prescribe TRT in several forms, each with different effects on hormone levels:

• Injections: Given every few days or weeks. They often create sharp peaks and drops in testosterone and DHT.

• Transdermal gels or patches: Applied daily to the skin. These provide more stable hormone levels but may slightly increase DHT due to skin enzyme activity.

• Pellets: Implanted under the skin and release testosterone slowly over months.

• Oral or buccal tablets: Less commonly used because of liver metabolism or irritation issues.

The route of administration matters because it can influence how much testosterone gets converted into DHT. For example, topical gels often lead to higher DHT levels in the skin compared to injections, since the 5-alpha-reductase enzyme is abundant in hair follicles and sebaceous glands.

Testosterone is a vital hormone that affects nearly every system in the body — from mood and muscle to bone and brain function. As men age, levels naturally decline, and some develop symptoms of low testosterone that require medical treatment. Testosterone Replacement Therapy can restore energy, libido, and strength, but it also shifts the balance of other hormones like DHT and estradiol.

Understanding how testosterone works — and how therapy changes the body’s natural balance — is key to grasping why some men notice changes in their hair growth patterns when on TRT. The next section will explain in more detail how testosterone converts to DHT and how that process connects to baldness risk.

The DHT Connection: How Testosterone Converts to Dihydrotestosterone

To understand why some people worry about losing hair while taking testosterone therapy, it helps to learn about a hormone called DHT, or dihydrotestosterone. DHT is made from testosterone inside the body. It is a powerful form of the hormone and plays a key role in both male development and hair loss. This section explains how testosterone turns into DHT, what DHT does in the body, and how it may affect the scalp and hair follicles.

How Testosterone Changes into DHT

Inside the body, an enzyme called 5-alpha-reductase (5AR) changes testosterone into DHT. An enzyme is a type of protein that speeds up chemical reactions. The 5-alpha-reductase enzyme is found in many tissues, including the skin, prostate, liver, and hair follicles.

There are two main types of this enzyme:

• Type I 5-alpha-reductase, found mostly in the skin, scalp, and sebaceous (oil) glands.

• Type II 5-alpha-reductase, found in higher amounts in the prostate, genitals, and also in the roots of hair follicles.

When testosterone enters cells that contain this enzyme, it can be converted into DHT. Once DHT is formed, it attaches to special proteins inside cells called androgen receptors. These receptors act like “locks” that only certain hormones can “unlock.” When DHT binds to these receptors, it activates them and sends signals that affect how the cell behaves.

Why DHT Is Stronger Than Testosterone

Even though testosterone is the main male hormone, DHT is actually a stronger version of it. Scientists call it a more potent androgen, meaning it has a greater effect on tissues sensitive to male hormones. DHT binds more tightly to androgen receptors than testosterone does, and it stays attached longer. Because of this, DHT can create stronger and longer-lasting changes in certain body parts.

During puberty, DHT helps develop male features such as a deeper voice, facial hair, and the growth of the penis and prostate. However, in adulthood, DHT can also play a role in some conditions related to hormones, like prostate enlargement and androgenetic alopecia (male pattern baldness).

The Role of DHT in Hair Follicles

Each hair on your head grows from a small structure under the skin called a hair follicle. Hair follicles go through three main phases:

1. Anagen (growth phase) – when the hair actively grows.

2. Catagen (transition phase) – when growth slows and the follicle begins to shrink.

3. Telogen (resting phase) – when the hair eventually falls out and the cycle starts again.

DHT can attach to androgen receptors located in the hair follicle, especially on the scalp. In people who are genetically sensitive to DHT, this hormone causes the follicle to shrink over time, a process known as miniaturization. The follicle then produces thinner, shorter, and weaker hair strands. Eventually, the follicle can stop growing visible hair altogether.

This process happens most often in certain scalp areas — usually the front hairline and the crown — where androgen receptors are more concentrated. This pattern is why the condition is called male pattern baldness.

Serum DHT vs. Scalp DHT

When doctors measure DHT levels through blood tests, they are measuring serum DHT, or the amount of DHT circulating in the bloodstream. But the DHT that affects hair loss mostly acts locally inside the scalp, not just in the blood. Hair follicles can produce their own DHT using the 5-alpha-reductase enzyme that exists inside them. This means that even if someone’s blood test shows normal DHT levels, the scalp itself might still have high local DHT activity.

Some studies have found that people with male pattern baldness often have higher levels of DHT or 5-alpha-reductase enzyme activity in their scalp compared to people who don’t lose hair. However, other research shows that total blood DHT may not always be much higher. This suggests that local sensitivity, rather than total DHT amount, plays the bigger role.

What This Means for Testosterone Therapy

When someone takes testosterone therapy (TRT), the amount of testosterone in the blood rises. Because the 5-alpha-reductase enzyme is present in many tissues, some of this extra testosterone may be converted into more DHT. This is a normal process. However, how much DHT increases depends on several factors:

• The person’s genetic makeup.

• The type and dose of testosterone therapy.

• The activity of the 5-alpha-reductase enzyme in the skin and scalp.

• The body’s natural balance of other hormones, such as estrogen and SHBG (sex hormone binding globulin).

In some men, this extra conversion can raise DHT levels enough to trigger or speed up hair thinning — but only if they already have a genetic sensitivity to DHT. In men who are not genetically prone to baldness, increased DHT from TRT usually does not cause significant hair loss.

DHT is a natural product of testosterone and an important part of male biology. It is created by the 5-alpha-reductase enzyme and acts more strongly than testosterone on tissues with androgen receptors. In genetically sensitive hair follicles, DHT causes gradual shrinkage and shorter hair growth cycles, leading to male pattern baldness. While testosterone therapy can raise DHT levels, it does not automatically cause baldness in everyone. The key factor is how each person’s hair follicles respond to DHT — which depends on their genes, hormone balance, and local scalp sensitivity.

Male Pattern Baldness: Genetics, Hormones, and Mechanisms

Male pattern baldness, also known as androgenetic alopecia (AGA), is the most common cause of permanent hair loss in men. It affects about half of all men by age 50 and can start as early as the late teens or twenties. While testosterone therapy is often blamed for causing baldness, the truth is that the main cause of hair loss in men is genetics — not testosterone itself. To understand how testosterone therapy might influence hair, we first need to look at what actually causes AGA.

Genetic Predisposition: Why Some Men Go Bald and Others Don’t

Hair loss from male pattern baldness is inherited, meaning it runs in families. Scientists have discovered that certain genes make the hair follicles — the tiny structures that produce each hair — more sensitive to hormones called androgens. These include testosterone and a stronger version of it called dihydrotestosterone (DHT).

The most important gene linked to male pattern baldness is the androgen receptor (AR) gene, which sits on the X chromosome (inherited from the mother). The AR gene controls how strongly your hair follicles respond to androgens. If you inherit a version of the gene that makes your follicles more sensitive to DHT, you’re more likely to lose hair as you age.

However, baldness is polygenic, meaning that multiple genes — not just one — contribute to the risk. These genes can come from both your mother’s and father’s side. This is why baldness patterns can vary so widely between individuals, even within the same family.

The Role of Hormones in Hair Follicle Health

Hair growth follows a repeating cycle with three main phases:

1. Anagen phase – the active growth phase, which can last several years.

2. Catagen phase – a short transition period where growth stops.

3. Telogen phase – the resting phase before the hair eventually sheds.

In a healthy scalp, most hair follicles are in the anagen (growth) phase. But when DHT attaches to androgen receptors in genetically sensitive hair follicles — especially on the crown and temples — it shortens the anagen phase and makes the follicle produce thinner, shorter, and weaker hairs. Over time, these follicles shrink in a process called miniaturization. Eventually, the follicles stop producing visible hairs altogether.

Interestingly, not all scalp hairs react the same way to DHT. The hairs on the back and sides of the head are typically resistant to DHT, which is why these areas often retain hair even in advanced baldness. This difference in sensitivity explains the classic “M-shaped” receding hairline and thinning crown that characterize male pattern baldness.

How DHT Triggers Follicle Miniaturization

DHT is a powerful androgen formed when testosterone is converted by the enzyme 5-alpha-reductase. DHT binds to androgen receptors in hair follicles more strongly than testosterone does. When this happens in men with genetic sensitivity, several changes occur in the follicle:

• The growth phase becomes progressively shorter.

• The resting phase becomes longer.

• The follicle shrinks and produces finer “vellus-like” hairs instead of thick terminal hairs.

• Blood flow and nutrient delivery to the follicle decrease.

These changes are slow and cumulative. It can take years before noticeable hair thinning appears. Once follicles have miniaturized completely, regrowing hair naturally becomes very difficult.

How Genetics and Hormones Interact

It’s important to understand that testosterone alone does not cause baldness. Many men have high testosterone levels and keep a full head of hair throughout life. Baldness occurs when genetically vulnerable follicles are exposed to DHT over time. In other words, testosterone therapy might increase DHT levels, but only those who are genetically predisposed are likely to experience accelerated hair thinning as a result.

Scientists describe this process as a hormone–gene interaction. Your genes determine how sensitive your follicles are, while your hormones provide the “signal” that activates the process. This is why two men can take the same dose of testosterone — one might notice hair thinning, while the other experiences no change at all.

Other Contributing Factors

While genes and hormones are the main players, other factors can influence how quickly hair loss progresses:

• Age: Hair follicles become more responsive to DHT as men age.

• Stress and nutrition: Severe stress, illness, or nutrient deficiencies can trigger additional shedding, though this type of loss (called telogen effluvium) is usually temporary.

• Inflammation: Some research suggests that scalp inflammation may worsen follicle damage over time.

• Lifestyle and environment: Smoking, chronic stress, and poor diet can negatively affect scalp blood flow and overall hair health.

Male pattern baldness is a genetically driven condition influenced by DHT and androgen receptor sensitivity. DHT shortens the growth phase of hair follicles in genetically susceptible men, leading to gradual thinning and eventual baldness. The process is slow, progressive, and largely irreversible without medical intervention.

Testosterone therapy does not create this genetic sensitivity — it can only interact with it. Therefore, TRT might speed up hair loss in someone who is already predisposed, but it cannot cause baldness in a person whose follicles are resistant to DHT.

Understanding this distinction helps patients and physicians make informed choices. The key takeaway is simple: genes set the stage, and hormones play the role — but the script for baldness is written in your DNA.

Does Testosterone Therapy Increase DHT Levels? What Studies Show

When men start testosterone replacement therapy (TRT), one of the main questions that comes up is whether it raises dihydrotestosterone (DHT) levels — and if so, by how much. DHT is a powerful form of testosterone that plays an important role in male traits such as facial hair, deep voice, and sexual development. However, it is also the hormone most linked to male pattern baldness. Understanding how TRT affects DHT helps explain whether therapy may influence hair loss risk.

How Testosterone Becomes DHT

Testosterone is converted into DHT by an enzyme called 5-alpha-reductase. This enzyme is found in many tissues, including the skin, prostate, and hair follicles on the scalp. The conversion process is simple: testosterone enters these tissues and 5-alpha-reductase changes it into DHT. Once DHT is formed, it binds more strongly to androgen receptors than testosterone does — meaning it has a stronger biological effect.

Not everyone produces the same amount of DHT. Genetics, age, and even lifestyle factors such as diet or medications can affect how active the 5-alpha-reductase enzyme is. Some people’s bodies naturally convert more testosterone into DHT, which is one reason why some men lose hair while others keep it even with similar testosterone levels.

Why DHT Matters During TRT

When men receive TRT, they are increasing the amount of testosterone in their bloodstream. Because DHT comes from testosterone, it is reasonable to expect that DHT levels might rise as well. But the degree of this rise depends on several factors, including:

• The dose of testosterone used

• The form of TRT (such as injections, gels, or pellets)

• The body’s natural enzyme activity

High DHT levels are not always harmful, but research has connected increased DHT to scalp hair thinning in genetically prone men and to prostate tissue growth in some cases. For this reason, many doctors check both testosterone and DHT levels in men undergoing therapy, especially those with a family history of baldness or prostate issues.

How Much Does DHT Rise on TRT?

Clinical research has shown a clear pattern: DHT often increases when testosterone therapy begins, but the rise depends on how the testosterone is delivered.

1. Injectable testosterone (cypionate or enanthate):
   Studies show that when testosterone is injected every 1–2 weeks, DHT levels can temporarily rise by 30% to 70% above baseline. This is because injections cause testosterone to spike in the blood soon after administration, and the enzyme 5-alpha-reductase quickly converts part of that testosterone into DHT. Over time, these peaks level out, but they can still cause short-term increases in DHT.

2. Topical testosterone (gels or creams):
   Topical forms can raise DHT even more in some men. Because 5-alpha-reductase is highly active in the skin, applying testosterone directly to the skin increases local conversion to DHT. In some studies, DHT levels increased by up to 150% with long-term use of gels. However, total testosterone levels tend to be steadier with this method compared to injections.

3. Pellets or slow-release implants:
   Pellets provide a constant release of testosterone over several months. Research shows they produce a moderate, steady increase in DHT, typically less dramatic than gels but more sustained than injections. Men using pellets may not experience large hormonal peaks, which could mean less fluctuation in DHT-related effects.

Individual Differences and Hormone Balance

Not all men experience the same rise in DHT from TRT. Some have naturally low enzyme activity, so their DHT changes very little. Others have high enzyme activity and see a significant increase. Age, body fat, genetics, and liver function can all influence this balance. In addition, medications such as finasteride or dutasteride, which block 5-alpha-reductase, can reduce the conversion and keep DHT lower.

It’s also important to remember that DHT levels in the blood may not fully reflect DHT activity in the scalp. Hair follicle sensitivity depends more on how responsive the follicles are to DHT rather than the absolute amount in circulation. Some men with high DHT never go bald, while others with normal levels lose hair early due to genetic sensitivity.

What Research Studies Conclude

Most clinical studies agree on several key points:

• TRT usually raises DHT levels modestly, though the amount varies by method and dose.

• The increase is predictable, not extreme, and usually remains within the normal range for adult men.

• Higher DHT does not always mean faster hair loss, especially if a man does not have the genes for androgen sensitivity.

• Men using topical gels tend to show the largest DHT rises, but this does not always result in visible hair thinning.

• Long-term studies have not shown that TRT causes new baldness in men without a genetic tendency for male pattern hair loss.

Testosterone therapy can increase DHT, but not always enough to cause baldness. The size of the increase depends on the form of therapy and on individual biology. Men who are already genetically sensitive to DHT may notice faster hair thinning when on TRT, while others may see little to no change. The relationship is complex and best monitored through regular blood tests and medical follow-ups.

Can TRT Trigger or Accelerate Baldness? Evidence from Clinical Research

Many men worry that testosterone replacement therapy (TRT) might make them go bald faster. The link between testosterone therapy and hair loss is often talked about online, but scientific studies show a more complex story. While testosterone can increase levels of a related hormone called dihydrotestosterone (DHT), which affects hair follicles, TRT does not directly cause baldness in everyone. Instead, it may speed up hair loss in men who are already genetically prone to male pattern baldness.

Understanding How TRT Could Affect Hair

TRT raises the amount of testosterone circulating in the body. Some of this extra testosterone is naturally converted into DHT by an enzyme called 5-alpha-reductase. DHT binds to receptors in hair follicles, especially those on the scalp’s crown and hairline. In men who are sensitive to DHT, this can cause the follicles to shrink over time. The result is thinner hair, shorter growth cycles, and eventually, visible baldness.

However, not all men’s hair follicles are equally sensitive to DHT. Genetics plays the biggest role. Men with certain variations in the androgen receptor (AR) gene are more likely to lose hair as DHT levels rise. If a man does not have this genetic predisposition, even high DHT levels from TRT may not cause noticeable thinning.

What Clinical Studies Have Found

Research has explored whether testosterone therapy truly changes hair patterns. A few studies have found that TRT slightly raises blood DHT levels, but the increase varies based on how the testosterone is given. For example, one study published in the Journal of Clinical Endocrinology & Metabolism found that men using testosterone gel had DHT levels increase by about 40%, while those receiving injections had smaller changes. Despite these increases, researchers did not find a clear pattern of new or rapid hair loss among participants.

In another clinical review, scientists looked at data from men on long-term TRT (over one year). They found that some experienced mild hair thinning, but most cases were in men who already showed early signs of baldness before therapy. This suggests that TRT may “unmask” genetic hair loss earlier rather than create new baldness on its own.

A 2017 study also showed that men with low testosterone who started TRT and had no family history of baldness did not experience significant hair changes after one year of treatment. This supports the idea that the therapy alone is not the cause — genetics and DHT sensitivity must both be present for hair loss to occur.

Correlation vs. Causation

When talking about hair loss and hormones, it’s important to separate correlation from causation. Just because two things happen together does not mean one causes the other. For example, many men begin TRT around middle age — the same period when male pattern baldness typically becomes more visible. This timing can make it seem like the therapy triggered the hair loss, even if it was already going to happen naturally.

Doctors often emphasize this point: TRT might speed up a process that was already underway, but it usually doesn’t start it. That is why two men on identical TRT doses can have completely different experiences — one may keep a full head of hair, while the other notices thinning within months.

Factors That Influence Hair Loss Risk

Several factors can affect whether TRT leads to visible hair changes:

• Genetic predisposition: The most powerful predictor of baldness.

• Age: Hair follicles become more sensitive to DHT over time.

• Baseline DHT and testosterone levels: Some men naturally convert more testosterone into DHT.

• Form of TRT: Gels and creams often increase DHT more than injections or pellets.

• Dosage: Higher doses raise both testosterone and DHT more sharply.

Doctors usually monitor hormone levels and symptoms during treatment to help balance benefits and side effects. If DHT becomes very high, adjustments to dose or form can be made.

What Long-Term Data Suggests

Long-term follow-up studies show that the majority of men on TRT do not go bald because of therapy alone. Hair loss, when it happens, tends to occur in those who were already predisposed to it. Importantly, other body hair (such as beard or chest hair) may thicken during TRT because DHT has different effects on those follicles.

Researchers also note that TRT can sometimes restore hair growth in men whose hair loss was linked to low testosterone rather than genetic baldness. This further shows how hormone effects vary from person to person.

Scientific evidence does not support the idea that TRT universally causes baldness. Instead, testosterone therapy may raise DHT slightly, and in men who already carry genes for androgenetic alopecia, this rise can make hair thinning appear sooner or progress faster. For others, there may be no change at all.

TRT can amplify a genetic tendency but does not create it. For men concerned about hair loss, working with a physician to monitor hormone levels and scalp health is the best way to understand their individual risk.

Distinguishing Normal Shedding from Hormonal Hair Loss During TRT

When men start testosterone therapy (TRT), some notice more hair falling out during the first few months. This can feel alarming and may raise fears of going bald quickly. However, not all hair loss during TRT means permanent baldness. In fact, there are different reasons hair can fall out — and understanding them helps people separate temporary shedding from true hormonal or genetic hair loss.

This section explains these differences in simple terms, explores what’s happening inside the scalp, and shows how doctors tell the two apart.

Temporary Hair Shedding: Telogen Effluvium

One common cause of hair loss that can happen after starting TRT is called telogen effluvium (TE).
This is a temporary form of hair shedding that occurs when many hairs enter the resting phase (called the telogen phase) of the hair growth cycle at the same time. Normally, about 5–10% of scalp hairs are in this resting phase, while the others are growing. But certain triggers — including hormonal shifts, stress, illness, or medications — can push up to 30–50% of hairs into resting mode.

When these hairs fall out a few weeks or months later, people notice more hair in the shower drain, on pillows, or when combing. The hair might seem thinner, but this type of shedding does not destroy hair follicles. Once the body adjusts and the growth cycle normalizes, new hairs grow back.

In the case of testosterone therapy, hormonal adjustment is the main trigger. TRT can quickly change levels of testosterone, dihydrotestosterone (DHT), and estradiol in the body. The scalp and hair follicles need time to adapt. Because of this, some men experience telogen effluvium about 2 to 4 months after starting TRT, but it usually improves within 6 to 12 months.

Key signs that point to telogen effluvium include:

• Sudden, even hair shedding across the entire scalp (not just the hairline).

• No visible bald patches or receding areas.

• Hair that feels thinner but still covers the scalp evenly.

• Regrowth visible as short new hairs after several months.

Hormonal or Genetic Hair Loss: Androgenic Alopecia

In contrast, androgenic alopecia (AGA) — also called male pattern baldness — is caused by a mix of genetic sensitivity and hormone activity, especially DHT.
Men who have certain genes in their androgen receptor (AR) are more sensitive to DHT. Even normal amounts of DHT can shrink hair follicles over time. These miniaturized follicles then produce shorter, finer hairs until they eventually stop producing visible strands.

When someone starts TRT, testosterone levels rise and may also increase DHT levels through an enzyme called 5-alpha-reductase. If a man already carries the genetic risk for AGA, this can speed up hair thinning in typical patterns: a receding hairline, thinning at the temples, or loss at the crown.

Unlike telogen effluvium, AGA usually develops gradually and is not reversible without treatment. However, progression can be slowed or stabilized with medical therapy under a doctor’s care.

Key signs that suggest androgenic alopecia include:

• Gradual thinning around the temples, crown, or top of the head.

• A family history of baldness on either side of the family.

• Fine, thin, or shorter hairs replacing once-thick strands in affected areas.

• Hairline that keeps moving back over time.

How Doctors Tell the Difference

Doctors use a combination of history, examination, and testing to figure out which type of hair loss is happening.

Medical and hormone history

A healthcare provider will ask when TRT began, which form is being used (injections, gels, or pellets), and how fast symptoms developed. They’ll also ask about recent illnesses, stress, diet, or other medications that might cause shedding.

Scalp examination and trichoscopy

Dermatologists may use a special magnifying camera (trichoscope) to look at the scalp closely. In telogen effluvium, hairs look normal but are fewer in number. In androgenic alopecia, doctors can see miniaturized follicles and different hair shaft sizes in the affected areas.

Laboratory testing

Blood tests can check hormone balance and possible contributing factors. Common tests include:

• Total and free testosterone

• DHT (dihydrotestosterone)

• Sex hormone-binding globulin (SHBG)

• Estradiol

• Thyroid hormones

• Iron and ferritin levels

These results help identify whether TRT is causing hormonal shifts that could trigger temporary shedding or if long-term DHT sensitivity is the main issue.

When to Seek Medical Advice

It’s normal to see some increased shedding within the first few months of TRT. However, men should talk to their doctor if:

• Hair loss is patchy or worsening rapidly.

• There are visible bald spots or itching on the scalp.

• Hair continues to thin for more than 6–9 months after starting TRT.

An endocrinologist or dermatologist can help determine whether adjustments to TRT dosage, 5-alpha-reductase inhibitors, or topical treatments are appropriate.

Monitoring Hormone and Scalp Health During Testosterone Therapy

Keeping track of your hormone levels and scalp health while on testosterone replacement therapy (TRT) is an important part of making sure treatment stays safe and balanced. Many men focus only on how they feel — more energy, better mood, or higher libido — but it’s just as important to monitor what’s happening inside the body and how it affects the skin and hair. Testosterone therapy changes the hormonal environment, and regular testing helps doctors adjust the dose, prevent side effects, and catch any unwanted shifts early.

Why Monitoring Matters

When testosterone is added to the body through therapy, some of it naturally converts to other hormones, such as dihydrotestosterone (DHT) and estradiol (E2). Each of these plays a role in how the body functions. DHT supports certain male features but is also the hormone most linked to male-pattern baldness. Estradiol, which is a form of estrogen, helps with mood, joint health, and sexual function, but too much or too little can cause symptoms.

Without monitoring, these hormone levels can move outside of a healthy range. A man might start TRT with normal DHT levels, but as treatment continues, DHT can rise sharply in some individuals, depending on genetics, dose, and how the testosterone is given. Tracking these numbers allows the healthcare provider to make small adjustments before problems such as scalp thinning or oily skin develop.

Key Hormones and Lab Markers to Check

Doctors usually recommend checking several blood tests regularly during TRT. Each marker gives clues about how the treatment is working and whether any imbalances might contribute to hair loss or other side effects.

1. Total Testosterone – This measures all testosterone in the blood, including both the bound and unbound forms. It helps determine if the therapy dose is high enough or too strong.

2. Free Testosterone – This is the active form of testosterone that the body can use directly. It is often more useful than total testosterone for understanding how much hormone is truly available to tissues like hair follicles.

3. Dihydrotestosterone (DHT) – Since DHT is created when testosterone is converted by the enzyme 5-alpha-reductase, monitoring it shows how much androgen activity is occurring. A sharp rise in DHT could explain new or worsening hair loss during TRT.

4. Sex Hormone-Binding Globulin (SHBG) – SHBG controls how much testosterone and DHT are free in the bloodstream. Low SHBG means more active hormones, which can increase the effect on hair follicles.

5. Estradiol (E2) – This is checked because testosterone can also convert into estradiol. Both too high and too low estradiol can cause side effects, and it may indirectly affect hair growth through changes in skin oil and inflammation.

6. Hematocrit and Hemoglobin – Although these do not affect hair directly, high levels can indicate that testosterone is too high overall, which may increase other androgen-related effects.

Regular lab work — usually every 3 to 6 months after starting TRT, and then once or twice a year once levels are stable — helps keep these markers in balance.

Watching for Changes in Scalp and Hair

Lab numbers tell part of the story, but paying attention to physical changes on the scalp is equally important. Hair responds slowly to hormones, so early signs can be subtle. Men should look for:

• Increased hair shedding when washing or combing.

• Thinning at the crown or temples, especially if there’s a family history of baldness.

• Changes in scalp oiliness or acne, which may indicate rising DHT activity.

• Irritation or itchiness on the scalp, which can accompany inflammation from hormonal shifts.

Dermatologists or trichologists (hair specialists) can perform scalp examinations or trichoscopy, a noninvasive imaging test that shows follicle health. Comparing photos over time also helps track slow changes.

Personalized Dosing and Medical Follow-Up

Not every man’s body reacts the same way to testosterone therapy. Some convert more testosterone into DHT than others. That’s why monitoring results should guide a personalized treatment plan. Doctors might adjust the TRT dose, change the delivery method (for example, switching from injections to gels), or use lower, more frequent doses to maintain steadier hormone levels.

If DHT levels rise significantly and hair loss becomes noticeable, physicians sometimes work with dermatologists to co-manage care. In some cases, they may suggest topical treatments or DHT-blocking medications — but only if the patient’s overall hormonal balance and health goals allow it. The goal is not to stop testosterone therapy, but to find a balance where the benefits of TRT are maintained without worsening hair loss.

Why Professional Oversight Is Essential

Attempting to adjust TRT dosage or add hair-loss medications on your own can create hormonal imbalances or interfere with other systems. Professional oversight ensures that hormone levels are interpreted correctly in context — not just from a single lab result. Doctors also look for side effects beyond the scalp, such as changes in cholesterol, liver function, or blood thickness.

Monitoring hormones and scalp health during testosterone therapy is not only about preventing baldness; it’s about maintaining overall hormonal balance and long-term well-being. Regular blood tests, scalp checks, and communication with healthcare providers help catch early signs of imbalance before they become visible problems. For most men, staying aware and adjusting treatment under medical supervision leads to the best outcome — steady testosterone levels, healthy hair where possible, and peace of mind knowing their therapy is managed safely.

Key Takeaways from Scientific Literature

The relationship between testosterone replacement therapy (TRT) and baldness is complex. Many people worry that taking testosterone will automatically make them lose their hair, but research shows the truth is not that simple. The studies that have explored this topic give us a more balanced picture: TRT may slightly increase the levels of dihydrotestosterone (DHT), which can speed up hair loss in men who are already genetically prone to male pattern baldness, but it does not cause baldness in everyone.

Let’s look closely at what the scientific evidence really tells us.

What Most Studies Agree On: DHT Levels Can Rise with TRT

Testosterone is converted into DHT through the enzyme 5-alpha-reductase. DHT is a more potent form of testosterone that binds strongly to receptors in the hair follicles and prostate. Because of this, DHT plays an important role in both normal male development and androgen-related changes, such as baldness and body hair growth.

Clinical studies show that when men start TRT, DHT levels usually increase.
For example:

• Some studies report that DHT levels can rise 30–60% within the first few months of therapy.

• Others show that the amount of increase depends on the dose and form of testosterone. Gels and creams, which are absorbed through the skin, can produce a more pronounced rise in DHT because the skin contains more 5-alpha-reductase enzymes.

• Injections, on the other hand, often lead to higher spikes in total testosterone but not always in DHT.

However, an increase in blood DHT does not automatically mean that hair loss will follow. The most important factor remains how sensitive a person’s hair follicles are to DHT — something controlled by genetic variation.

Genetics Plays the Main Role

Research shows that androgenetic alopecia (AGA), or male pattern baldness, is driven mainly by genetic sensitivity to DHT rather than by DHT levels alone. Some men can have high testosterone and DHT levels their whole lives without losing significant hair, while others with normal hormone levels may go bald at a young age.

The difference lies in the androgen receptor gene (AR gene), located on the X chromosome. This gene controls how strongly hair follicles respond to DHT. If someone inherits a version of the AR gene that makes the receptors more sensitive, even normal DHT levels can gradually shrink the follicles over time.

Therefore, TRT does not “cause” baldness — it can only speed up a process that was already determined by genetics.

Not Everyone on TRT Experiences Hair Loss

Multiple clinical reports and patient follow-ups show that many men on TRT experience no change in their hairline over several years. In some cases, men with low testosterone who begin therapy actually report improved hair thickness on the body or scalp, likely because restoring normal hormone balance supports overall hair growth cycles.

What this means is that hair loss during TRT is not a universal side effect — it happens mostly to those with a hereditary predisposition. It’s also important to note that age plays a role. Middle-aged or older men who begin TRT may already be at the stage where their genetic pattern of hair loss is naturally progressing, regardless of therapy.

Evidence from Systematic Reviews and Long-Term Studies

So far, the medical literature contains a mix of short-term and long-term studies:

• Short-term studies (lasting 6–12 months) show a modest increase in serum DHT but not enough data on visible hair changes.

• Long-term observational studies (2–5 years) do not show consistent or significant acceleration of baldness.

For instance, in one study following men on TRT for several years, researchers found no statistically significant difference in the rate of hair thinning compared with men not on therapy — once genetic risk factors were accounted for. Another systematic review published in endocrinology journals noted that no controlled studies confirm a direct causal link between TRT and new-onset baldness.

However, the authors emphasized that in men who already show early signs of AGA, TRT may amplify that pattern through sustained higher DHT exposure, especially if DHT levels are not regularly monitored.

The Need for Ongoing Research

Despite decades of testosterone research, very few studies focus specifically on scalp hair outcomes. Most clinical trials are designed to measure testosterone’s effects on libido, energy, muscle mass, and bone density, not hair growth or loss.
This means more targeted studies are needed — particularly those that:

• Track scalp DHT levels rather than just blood levels.

• Compare hair outcomes across different TRT forms (gels, injections, pellets).

• Include both men and women receiving testosterone therapy.

As researchers better understand how testosterone and DHT interact in the scalp, doctors will be able to offer clearer guidance about hair-related risks.

What Readers Can Take Away

From the existing scientific evidence, several key conclusions can be made:

1. TRT increases DHT modestly, especially with topical forms.

2. DHT contributes to male pattern baldness, but only in genetically sensitive individuals.

3. TRT does not cause baldness by itself, though it can make hereditary hair loss appear sooner or progress slightly faster.

4. Individual response varies widely — not everyone experiences hair changes.

5. Regular monitoring of hormone levels, along with open communication between patient and physician, is the best way to manage potential side effects.

Scientific studies reveal that testosterone therapy and baldness are linked by DHT, but the relationship depends heavily on genetics. TRT may raise DHT, yet the degree of increase is usually within the normal physiological range. For most people, that alone is not enough to trigger hair loss.

The current evidence supports a balanced conclusion: TRT is not a universal cause of baldness, but it may influence hair loss in those already predisposed. Continued research and individualized medical management can help ensure that the benefits of hormone therapy are achieved without unexpected effects on hair health.

Conclusion: Balancing Hormonal Health and Hair Preservation

Testosterone Replacement Therapy (TRT) has become a common treatment for men who have low testosterone levels. Many men turn to it for help with fatigue, low mood, reduced muscle mass, and a drop in sexual function. For many, TRT can restore energy, improve mood, and boost physical performance. However, one of the most frequent concerns about testosterone therapy is the fear of going bald. It’s understandable — hair is an important part of appearance and self-confidence, and losing it can cause stress. The connection between testosterone therapy and hair loss is complex, and the truth is that TRT does not automatically make everyone lose their hair. The outcome depends on many factors, including genetics, hormone sensitivity, and how the body converts testosterone into other forms, such as dihydrotestosterone (DHT).

The science behind this issue shows that testosterone itself is not the direct cause of baldness. Instead, DHT — a hormone made when testosterone is converted by an enzyme called 5-alpha-reductase — plays the key role. DHT attaches to receptors in hair follicles, especially those located on the top and front of the scalp. In people who are genetically sensitive to DHT, this can make the follicles shrink over time, producing thinner and shorter hairs. Eventually, the follicles can stop producing hair completely. This process is known as androgenetic alopecia, or male pattern baldness. It is largely inherited, meaning some men’s hair follicles are more likely to react to DHT than others.

When a man starts TRT, his testosterone levels increase, and so can his DHT levels. However, this rise in DHT does not automatically mean that every man will lose hair. For men who do not have a genetic tendency for hair loss, the extra DHT is unlikely to cause noticeable thinning. For men who already have that genetic sensitivity, TRT may speed up a process that was already going to happen naturally. In other words, testosterone therapy might “reveal” a preexisting risk rather than create a new one.

Research studies suggest that while some men on TRT notice faster hair loss, many others experience no change at all. The response seems to vary greatly among individuals. Scientists believe that the dose and method of testosterone administration may also play a role. For example, injections can lead to higher short-term testosterone and DHT spikes compared to gels or patches. But even then, these effects are not consistent enough to claim that one form always causes more hair loss than another. What matters most is how the person’s body processes and responds to those hormones.

The relationship between TRT and baldness is, therefore, best seen as a balance between hormones and genetics. This balance can be managed with medical guidance. Men who are concerned about hair loss while on TRT can talk to their doctors about monitoring their hormone levels, including testosterone, DHT, and sex hormone-binding globulin (SHBG). Some may also consider safe, evidence-based medications that reduce scalp DHT levels without lowering the benefits of TRT. This should always be done under medical supervision, as hormone management is complex and requires precision.

It’s important to remember that testosterone therapy has proven benefits beyond cosmetic concerns. Restoring healthy testosterone levels can improve bone strength, muscle maintenance, and mental well-being. These health improvements often outweigh the potential for mild hair thinning in genetically sensitive individuals. At the same time, managing appearance-related effects is part of maintaining confidence and quality of life. This is why open communication between patients and healthcare providers is so important.

The main takeaway from the scientific literature is clear: TRT does not universally cause baldness. It may, however, slightly increase the risk of hair loss in men who already have a family history of male pattern baldness. The key difference lies in genetic sensitivity to DHT. Men who are predisposed will likely lose hair eventually, whether or not they take testosterone therapy. TRT might make the process occur a little faster, but it does not create baldness from nothing.

In conclusion, testosterone therapy and baldness are linked through a chain of biological and genetic factors. The hormone itself is not the enemy; it’s the way some hair follicles respond to its byproducts. For men considering TRT, the best approach is an informed one — understanding personal risks, discussing options with a healthcare provider, and monitoring hormonal balance over time. With proper medical supervision, it’s possible to enjoy the many health benefits of TRT while taking steps to preserve hair health. The goal is not to choose between hormones and hair but to find a balance that supports both physical vitality and personal confidence.