Estrogen therapy increases sex hormone binding globulin and, like aging men, this reduces the amount of free, active testosterone in the body. It's one of several androgens (male sex hormones) in females. Testosterone serves as the primary male sex hormone, influencing everything from muscle mass and bone density to mood, cognitive function, and sexual health. Abnormal testosterone levels can affect overall health, mood, and physical capabilities when left unaddressed.
The allure of effortlessly packing on muscle mass fuels the popularity of testosterone boosters. Testosterone promotes the development of the secondary sex characteristics in men and serves to maintain the function of the prostate and seminal vesicles. In men, testosterone is synthesized almost exclusively by the Leydig cells of the testes.
When testosterone-deprived rats were given medium levels of testosterone, their sexual behaviours (copulation, partner preference, etc.) resumed, but not when given low amounts of the same hormone. 2020 guidelines from the American College of Physicians support the discussion of testosterone treatment in adult men with age-related low levels of testosterone who have sexual dysfunction. On average, in adult males, levels of testosterone are about seven to eight times as great as in adult females. In humans, testosterone plays a key role in the development of male reproductive tissues such as testicles and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair. For women, the goal is to avoid supraphysiologic exposure and maintain levels within the normal female range if therapy is used at all (Travison et al., Journal of Clinical Endocrinology & Metabolism, 2017; Davis et al., Journal of Sexual Medicine, 2019). For women, testosterone therapy has a much narrower evidence-based use case, and treatment should remain within the female physiologic range rather than approach male-style replacement targets (Mulhall et al., Journal of Urology, 2018; Davis et al., Journal of Sexual Medicine, 2019).
Resistance training, especially compound movements like squats and deadlifts, stimulates testosterone production. Sleep deprivation can reduce testosterone by 15% or more in just one week. Laboratory reference ranges are determined by population statistics, not optimal health outcomes. There's an important distinction between "normal" (within reference range) and "optimal" (where you feel and function best). Fasting is recommended since eating can temporarily affect levels. For accurate results, testosterone should be drawn before 10 AM. Testosterone follows a circadian rhythm, with levels highest in the early morning (6-10 AM) and declining throughout the day by 20-30%.
You may also consider natural ways to increase testosterone levels. Your doctor can help confirm the results, or they may order additional tests to understand what factors could be causing your low or high hormone levels. If you’re concerned about your reproductive health or are experiencing any of the symptoms of having high or low testosterone, it may be a good idea to speak with a doctor.
Adolescent boys with too little testosterone may not experience normal masculinization. A "feedback loop" closely regulates the amount of hormone in the blood. They travel from one organ or another place in the body, usually through the bloodstream, and affect many different bodily processes. Learn all about the sex hormone here, including its primary benefits. What's more, testosterone plays other important roles in health and disease that may surprise you. Learn why free testosterone matters and what your levels mean. However, these changes may not fully restore levels in men with significant deficiency or underlying medical conditions.
Pharmacies and various companies may sell at-home testosterone tests. Your healthcare provider will consider your medical history and current medications when they review your results. When you get your blood test results back, there will be information that indicates what that lab’s normal ranges are.