Men’s Health
Video 01 — What Are Male Hormones?
Male hormones usually refers to androgens, including testosterone. Although present in everyone, their levels differ. In men, the testicles produce most testosterone under signals from the brain and pituitary gland. During puberty, testosterone supports voice changes, facial hair, muscle development, and reproductive maturation. In adulthood, it helps maintain sexual desire, muscle, bones, and red blood cell production. Other hormones matter too. DHT influences prostate development and hair growth, while estradiol supports bone health. Hormones work together rather than independently. Fatigue, mood changes, or reduced motivation can have many causes and do not, by themselves, establish that someone has low testosterone.
Video 02 — Testosterone: More Than a Sex Hormone
Testosterone supports far more than sexual desire. It helps maintain muscle, bone strength, red blood cell production, and reproductive function. In men, the testicles produce most testosterone, guided by signals from the brain and pituitary gland. Women also produce smaller amounts. Levels fluctuate throughout the day and can change with aging, illness, poor sleep, obesity, and medications. More testosterone does not automatically improve health or energy. Fatigue or reduced motivation alone cannot establish a deficiency. Evaluation considers symptoms alongside appropriately timed blood tests, usually repeated to confirm low levels. Treatment decisions require understanding the cause, potential benefits, and possible risks.
Video 03— Where Do Male Hormones Come From?
Male hormones are produced through teamwork between the brain, testicles, and adrenal glands. The hypothalamus releases GnRH, which signals the pituitary gland to release LH and FSH. LH stimulates Leydig cells in the testicles to make testosterone, the main androgen in men. FSH acts on Sertoli cells and works with testosterone to support sperm production. The adrenal glands above the kidneys produce smaller amounts of androgens, including DHEA and androstenedione. Other tissues can convert these into more active hormones. Feedback signals help the brain adjust hormone production, maintaining a balance that supports reproductive function and other essential processes throughout adulthood.
Video 04— How Does the Brain Control Testosterone?
Testosterone production starts with signals from the brain. The hypothalamus releases gonadotropin-releasing hormone, or GnRH, in regular pulses. These signals tell the pituitary gland beneath the brain to release luteinizing hormone, or LH. LH travels through the bloodstream to the testicles, where it stimulates Leydig cells to produce testosterone. As testosterone levels rise, feedback signals reduce further stimulation from the hypothalamus and pituitary. When levels fall, stimulation can increase. This feedback loop helps regulate hormone production. Sleep, illness, stress, and certain medications can influence this system, which is why testosterone levels may change across the day and over time.
Video 05— Why Men Need Estrogen Too
Estrogen is essential for men as well as women. In men, an enzyme called aromatase converts some testosterone into estradiol, an important form of estrogen. This happens in tissues including body fat, bone, and the brain. The testicles also contribute. Estradiol helps maintain strong bones by regulating the balance between bone breakdown and formation. Insufficient estrogen can contribute to bone loss and fractures. Together with testosterone, estrogen also supports sexual desire and reproductive function. However, libido depends on many physical and psychological factors. A change in sexual desire alone does not show whether estrogen levels are low, normal, or high.
Video 06— Testosterone and DHT: What Is the Difference?
Testosterone and dihydrotestosterone, or DHT, are androgens with related but different roles. Testosterone is produced mainly in the testicles and supports sexual desire, muscle maintenance, bone health, red blood cell production, and sperm production. DHT forms when the enzyme 5-alpha reductase converts testosterone in tissues such as skin, hair follicles, and the prostate. DHT activates androgen receptors more strongly than testosterone and helps shape male genital development, facial hair, and prostate growth. In genetically susceptible men, it also contributes to scalp hair loss. Their effects depend on tissue sensitivity, local hormone conversion, and hormone levels, rather than blood levels alone.
Video 07— Total and Free Testosterone: What Do They Mean?
Total testosterone measures all testosterone circulating in the blood, including hormone attached to proteins and hormone circulating freely. Most testosterone binds to sex hormone-binding globulin, called SHBG, or albumin. Free testosterone is the small portion that remains unattached to these proteins. These measurements describe different aspects of the same hormone. Changes in SHBG can affect total testosterone without a matching change in free testosterone. This helps explain why the numbers sometimes appear inconsistent. Interpreting results requires attention to symptoms, testing methods, timing, and the laboratory’s reference ranges. Neither measurement alone provides a complete picture of hormonal health or overall well-being.
Video 08— Why Testosterone Changes Throughout the Day
Testosterone levels naturally rise and fall throughout the day. In men who sleep at night, levels generally increase during sleep, peak around early morning, and decline afterward. This daily pattern is often stronger in younger men and becomes less pronounced with age. The brain helps coordinate these changes through signals between the hypothalamus, pituitary gland, and testicles. Hormonal messages arrive in pulses, creating fluctuations alongside influences from sleep and the body’s internal clock. Disrupted sleep and shift work can alter this pattern. Because timing affects results, testosterone measurements taken at different hours may show different numbers without indicating a disorder.
Video 09— Male Puberty: Changes Driven by Hormones
Male puberty marks the transition toward physical and reproductive maturity. It usually begins between ages nine and fourteen and develops gradually over several years. The process starts when the hypothalamus increases pulses of GnRH, signaling the pituitary gland to release LH and FSH. LH stimulates the testicles to produce testosterone, while FSH and testosterone support sperm production. Hormonal changes contribute to genital growth, a deeper voice, increased muscle mass, and facial hair. Growth hormone and other signals also support the adolescent growth spurt. Timing varies between individuals, and changes occur in stages rather than appearing all at the same time.
Video 10— How Do Male Hormones Change With Age?
Male hormones change throughout life, with substantial differences between individuals. Testosterone rises sharply during puberty, supporting sexual development, muscle growth, and bone strength. Levels generally peak during adolescence and early adulthood, then tend to decline gradually with advancing age. However, this decline varies, and some older men maintain testosterone within normal ranges. Health conditions, obesity, sleep problems, and medications can also influence levels. Unlike menopause, male aging usually involves no sudden, universal end to reproductive hormone production. Testosterone production and sperm formation may continue into later life, although fertility can change. Age alone does not establish a testosterone deficiency diagnosis.