Dihydrotestosterone

Dihydrotestosterone, commonly known as DHT, is the most potent androgen in your body and plays a central role in male development and physiology. It is produced when the enzyme 5-alpha reductase converts testosterone into DHT, a process that occurs primarily in the prostate, skin, hair follicles, and liver. Although DHT is present at much lower circulating levels than testosterone, it binds to androgen receptors with roughly three to five times greater affinity, making it the dominant driver of androgen-dependent functions in specific tissues. DHT is essential for the development of male sex characteristics during puberty and continues to support sexual function, prostate health, and neurological wellbeing throughout life.

Think of DHT as the amplified version of testosterone, fine-tuned for specific jobs. While testosterone is the general-purpose androgen circulating throughout your body, DHT is the specialist that your tissues produce locally when they need a stronger signal. In the prostate, DHT drives glandular growth and function. In the brain, it serves as a precursor to neurosteroids like allopregnanolone, which modulate GABA receptors and are directly involved in mood regulation, stress resilience, and cognitive clarity. In the skin and hair follicles, DHT influences sebum production and, in genetically susceptible individuals, can contribute to androgenetic alopecia by triggering follicular miniaturisation. Crucially, DHT does not cause hair loss on its own; genetics determine follicle receptor sensitivity, which is why two men with identical DHT levels can have completely different hairlines.

DHT levels are influenced by several factors. Testosterone availability is the primary determinant, since DHT is derived from it, so anything that affects testosterone will indirectly affect DHT. The activity of 5-alpha reductase varies between individuals due to genetics, and it can be modified by medications such as finasteride and dutasteride, which block the enzyme and reduce DHT production by approximately 70 per cent. Body composition, insulin resistance, and liver function can all influence conversion rates. Age plays a role too, as 5-alpha reductase activity tends to increase in prostate tissue with age, contributing to benign prostatic hyperplasia. If your DHT result is outside the expected range, your GP can interpret it alongside testosterone, SHBG, and free testosterone to assess your overall androgen metabolism and discuss any implications.