Dihydrotestosterone (DHT) is a powerful sex hormone that drives male sexual development before birth, triggers many of the physical changes of puberty, and continues influencing your skin, hair, prostate, and muscles throughout adulthood. It binds to the same receptors as testosterone but grips them more tightly, making it the stronger androgen. That potency is why DHT is essential for normal development but also why excess levels cause problems like hair loss, acne, and prostate enlargement.
How Your Body Makes DHT
DHT is not released directly by the testes or adrenal glands. Instead, your body converts testosterone into DHT using an enzyme called 5-alpha reductase. Two versions of this enzyme exist. Type 1 is found mainly in the skin and liver, while Type 2 is concentrated in the prostate. Both versions produce DHT, but they do so in different tissues, which explains why DHT affects such a wide range of organs.
Once formed, DHT binds to androgen receptors inside cells more tightly than testosterone does. Inside the prostate, for example, DHT is present at higher concentrations than testosterone and is the dominant hormone driving cellular activity. This stronger binding is what makes DHT roughly two to three times more potent than testosterone at activating androgen-sensitive tissues.
DHT Builds Male Anatomy Before Birth
During fetal development, DHT is responsible for forming the external genitalia, urethra, and prostate. Testosterone alone isn’t enough. The fetus converts testosterone to DHT in specific tissues, and that DHT then shapes the urogenital structures into their male form. When this conversion fails, as it does in rare genetic conditions where 5-alpha reductase is missing, a genetically male baby can be born with ambiguous or female-appearing genitalia, despite having normal testosterone levels.
What DHT Does During Puberty
At puberty, rising testosterone levels mean more raw material for DHT production, and the effects are visible. DHT promotes further growth of the penis and scrotum, drives the appearance of facial hair, body hair, and pubic hair, and stimulates the prostate to grow. It also ramps up activity in the sebaceous (oil) glands of the skin, which is why acne tends to appear during the teenage years. Essentially, many of the traits people associate with male puberty, from a deepening voice to a first beard, depend on DHT rather than testosterone alone.
Muscle and Strength
DHT plays a more significant role in muscle than was once recognized. Research on isolated muscle fibers found that DHT increased protein synthesis and amino acid uptake in fast-twitch muscle fibers, while testosterone did not produce the same effect. Fast-twitch fibers are the ones responsible for explosive movements and strength. Some researchers have gone as far as calling DHT the main anabolic steroid in adult mammalian skeletal muscle, though both hormones clearly contribute to lean body mass in the real world.
How DHT Causes Hair Loss
The same hormone that grows your beard can thin the hair on your head. In androgenetic alopecia (pattern hair loss), DHT binds to receptors in scalp follicles and gradually shrinks them in a process called miniaturization. Over years, thick terminal hairs are replaced by finer, shorter strands that eventually stop growing altogether.
The mechanism is specific. DHT suppresses a signaling pathway that hair follicle stem cells rely on for regeneration. It also triggers the production of proteins that cause follicle cells to die off faster. The growth phase of the hair cycle shortens, so each strand has less time to develop fully, while the resting phase extends, meaning more follicles sit dormant at any given time. This combination of shorter growth and longer rest produces the gradual thinning that affects roughly half of men by age 50 and a significant number of women as well.
Notably, body and facial hair follicles respond to DHT in the opposite way, growing thicker and darker. The difference comes down to which genes are active in follicles at different body sites.
DHT and the Prostate
The prostate is one of the most DHT-sensitive organs. DHT drives prostate cell growth throughout life, which becomes a problem as men age. In benign prostatic hyperplasia (BPH), the prostate enlarges enough to compress the urethra and cause urinary symptoms like frequent urination, weak stream, and difficulty emptying the bladder.
Inside an enlarged prostate, DHT appears to do two things: it stimulates cells to multiply faster and it suppresses the normal process of programmed cell death that keeps tissue size in check. Research in animal models shows that genes promoting cell survival get turned up while genes triggering cell death get turned down, leading to a net increase in prostate tissue. DHT also activates a chronic inflammatory response within the prostate, which amplifies the growth signals further. This is why medications that block DHT production are a standard treatment for BPH and can measurably shrink the gland.
Skin, Oil, and Acne
Your skin contains both types of 5-alpha reductase and can produce DHT locally, independent of what’s circulating in your blood. DHT binds to receptors in sebocytes, the cells that make up your oil glands, and activates genes that increase sebum production. A marked increase in sebum is considered a necessary early step in acne development, because excess oil clogs pores and feeds the bacteria that cause inflammation.
DHT doesn’t just increase the amount of sebum. It also alters the composition of the oil, making it more likely to trigger breakouts. On top of that, DHT promotes inflammatory signaling within the oil glands themselves, compounding the problem. This is why hormonal acne treatments that reduce androgen activity tend to be effective, particularly in women.
DHT in Women
Women produce DHT too, just in smaller amounts. Healthy premenopausal women have average serum DHT levels around 9 ng/dL, compared to a typical male range of roughly 14 to 95 ng/dL. After menopause, women’s DHT drops to about 3 ng/dL.
When women produce excess androgens, DHT is often the downstream culprit behind visible symptoms. Within the hair follicle and oil gland, local conversion of testosterone to DHT amplifies androgen effects on the skin. This can cause adult acne, excess facial or body hair growth (hirsutism), and female pattern hair loss. About 20% to 30% of women with persistent adult acne also have hirsutism, and both symptoms are considered clinical signs of androgen excess. Polycystic ovary syndrome (PCOS) is the most common underlying cause, with most PCOS guidelines recognizing acne as a manifestation of elevated androgen activity.
Sexual Function and Mood
DHT’s role in sexual desire and mood is more nuanced than its role in physical tissues. A 24-month trial gave healthy older men DHT directly, which completely suppressed their testosterone and estrogen levels. Despite these dramatic hormonal shifts, the men reported no significant changes across 33 measures of sexual function and mood, with one exception: a mild decrease in overall sexual desire that reversed after treatment stopped. Age and body weight turned out to be far more important predictors of sexual function than DHT levels.
This suggests that while DHT can maintain many aspects of sexual function on its own, it is not the primary driver of libido in the way testosterone is often described. The relationship between androgens and sexual desire involves multiple hormones working together rather than any single one acting alone.
When DHT Levels Are Too High or Too Low
Elevated DHT is most commonly associated with pattern hair loss, acne, and prostate enlargement in men, and with hirsutism, acne, and hair thinning in women. Low DHT, on the other hand, can occur naturally due to 5-alpha reductase deficiency or as a result of medications designed to block the enzyme. Men taking these medications for hair loss or prostate problems typically see reduced scalp hair shedding and improved urinary symptoms, but some report side effects like reduced libido or changes in sexual function, consistent with DHT’s role in androgen-sensitive tissues throughout the body.
Normal serum DHT levels for adult men range from about 14 to 95 ng/dL depending on the laboratory and measurement method used. Because DHT acts primarily within tissues rather than circulating freely in large amounts, blood levels don’t always reflect what’s happening at the follicle or prostate level. This is one reason symptoms like hair thinning can progress even when blood DHT appears normal.