Testosterone is a vital hormone that plays a significant role in the development and maintenance of male and female characteristics. While it is predominantly produced in the testicles in males, females also produce smaller amounts in the ovaries and adrenal glands. Sex hormone-binding globulin (SHBG) is a glycoprotein primarily produced by the liver, although other tissues also contribute to its production. Its main function is to bind to sex hormones such as testosterone and estrogen in the bloodstream, regulating their distribution and bioavailability in the body. Testosterone influences various aspects of health, such as muscle mass, bone density, and the production of red blood cells, contributing to overall well-being and energy levels in both genders. A blood test for testosterone levels is valuable for assessing hormonal balance, helping individuals and healthcare professionals identify potential imbalances that may affect physical and mental health. Monitoring testosterone levels is particularly relevant for individuals experiencing symptoms like fatigue, low libido, or mood changes, as it can aid in the diagnosis and management of hormonal disorders in both men and women.
Total Testosterone: refers to the overall amount of testosterone in the bloodstream, including both bound and unbound forms of the hormone. Testosterone can exist in the blood in two main forms: bound to proteins (such as albumin or sex hormone-binding globulin, SHBG) or unbound (free testosterone). Total testosterone measurement encompasses both free and bound testosterone.
Free Testosterone: specifically refers to the unbound, biologically active form of testosterone in the bloodstream. While total testosterone provides an overall picture of the hormone's quantity, free testosterone is considered the fraction that is readily available for use by the body's tissues and cells. Free testosterone is crucial for various physiological functions, including muscle development, bone density, and sexual function.
SHBG: Sex Hormone Binding Globulin plays a critical role in regulating testosterone's impact on the body. This protein binds to testosterone in the bloodstream, acting as a reservoir and influencing its bioavailability. High levels lead to a larger portion of testosterone binds to it, leaving less "free" testosterone available to reach target tissues, in women however this may reduce the risk of PCOS (polycystic ovary syndrome). Low levels result in more free testosterone circulating, however if excessively low it may be associated with conditions like obesity, insulin resistance, and metabolic syndrome.
Too High a level of Testosterone is rare and often the result of exogenous steroid use. However a level consistently higher than the reference range may be caused by congenital conditions or a Pituitary Tumour. In women it may be a sign of Polycystic Ovary Syndrome. The following are symptoms, signs and consequences of excessively high testosterone:
Too Low a level of Testosterone is far more common, the following guidelines therefore focus on increasing testosterone levels. Levels far lower than the reference range may be caused by congenital conditions such as Klinefelter syndrome or a Pituitary Tumour. The following are symptoms, signs and consequences of excessively low testosterone:
A well balanced diet, including lean proteins, whole grains, various fruits, vegetables and legumes is ideal for not only general health but optimal testosterone levels. However supplementation can enhance one's ability to ensure they are consuming sufficient amounts of vitamins and minerals and addressing any dietary deficiencies to support testosterone synthesis. Note that excessive supplement use does not increase testosterone levels exponentially and may even detriment one's health.
Vitamin D | [more info] - a fat-soluble vitamin that plays a crucial role in testosterone synthesis by stimulating its production in the testes, regulating gene expression, maintaining sperm quality, reducing inflammation, and contributing to hormonal balance. Adequate vitamin D levels are essential for overall reproductive health and testosterone production. Note that most research suggests Vitamin D levels above the recommended level (75 nmol/l) show little to no benefit.
Zinc | [more info] - a mineral vital for testosterone production as it is a cofactor for key enzymes involved in the synthesis of testosterone. It plays a crucial role in the conversion of cholesterol into testosterone and helps regulate the activity of the pituitary gland, which signals the testes to produce testosterone. Ensuring sufficient zinc intake is important for supporting healthy testosterone levels.
Boron | [more info] - a mineral that supports testosterone production by enhancing the activity of enzymes involved in steroidogenesis. It may increase free testosterone levels by reducing sex hormone-binding globulin (SHBG), which binds to testosterone and makes it less available. Adequate boron intake contributes to maintaining healthy testosterone levels.
Magnesium | [more info] - a mineral that helps activate enzymes involved in the conversion of cholesterol into testosterone, influences the binding of testosterone to its receptors, and supports overall testicular function. Adequate magnesium levels are crucial for maintaining healthy testosterone levels in the body.
*Ashwaganda | [more info] - a popular herb in traditional medicine, often touted for its potential to support testosterone levels indirectly. Research suggests that ashwagandha may help reduce stress and cortisol levels, which in turn could support healthy testosterone production. However, direct evidence linking ashwagandha to testosterone elevation is limited and requires further investigation.
*Fadogia Agrestis | [more info] - a plant known for its traditional use in African herbal medicine, particularly for its potential effects on testosterone levels. Some studies suggest that Fadogia agrestis may have properties that could positively influence testosterone production. However, research on its efficacy and safety, especially in human subjects, remains limited and inconclusive. It's postulated that it may increase intratesticular cholesterol levels and lead to Leydig cell stimulation, however there are also concerns over testicular toxicity. Further scientific investigation is needed to better understand its mechanisms of action and potential benefits for testosterone regulation.
*Tongkat Ali | [more info] - a herb native to Southeast Asia, whcih some studies suggest that Tongkat Ali may have potential benefits for improving sperm quality, enhancing muscle strength, and boosting energy levels. However, the scientific evidence supporting its efficacy in testosterone enhancement is still limited and inconclusive. Some believe it may act like a SERM such as Clomiphene, blocking estrogen receptors in the hypothalamus to stimulate the production of LH & FSH. While Tongkat Ali is generally considered safe for short-term experimental use, long-term effects and safety remain unclear.
*These supplements are not typically found in a standard diet. They may exhibit pharmacological effects similar to medications and should be used with caution. It is essential to acknowledge that scientific research supporting the efficacy and safety of these supplements may be limited.
Cardiovascular Exercise: Engaging in cardiovascular exercise, such as running, cycling, or aerobic activities, contributes to maintaining healthy testosterone levels. Cardiovascular exercise helps manage body weight and fat, reducing the impact of obesity-related factors that can negatively affect testosterone. Additionally, it promotes overall cardiovascular health, which indirectly supports optimal hormonal balance. Note however that prolonged intense exercise for successive weeks, days and months can in fact lower Testosterone if recovery is not prioritised.
Resistance Training: Weight training, including resistance and strength training, is particularly effective in boosting testosterone levels. Intense resistance exercises, like weight lifting, stimulate the production of testosterone. The stress placed on muscles during weight training prompts the body to release more testosterone, fostering muscle growth and strength development. Regular weight training sessions contribute to a positive cycle of increased testosterone production and improved overall fitness.
Weight Management: Excess body fat, especially around the abdomen, can contribute to lower testosterone production. Adipose tissue, particularly visceral fat, promotes the conversion of testosterone to estrogen, which can further decrease testosterone levels. By adopting a balanced diet and engaging in regular physical activity, individuals can manage their weight effectively, helping to optimize testosterone production and overall hormonal balance.
Sleep & Stress Control: Sleep deprivation and chronic stress can disrupt hormone balance, leading to decreased testosterone production. During sleep, the body undergoes essential processes for hormone regulation and repair. Consistent, restful sleep supports testosterone synthesis and overall hormonal health. Similarly, managing stress through relaxation techniques, regular exercise, and mindfulness practices can help reduce cortisol levels, the stress hormone, and support testosterone production.
Alcohol & Substance Abuse: Excessive alcohol consumption can disrupt hormone production and metabolism, leading to decreased testosterone levels over time. Additionally, certain drugs, including anabolic steroids and opioids, can interfere with the body's natural hormone regulation, potentially causing testosterone imbalances. It's essential to consume alcohol and medications responsibly and to avoid substance abuse to maintain optimal testosterone levels and overall health.
The relationship between mental health issues (ie. depression) and testosterone levels is complex and bidirectional. Both low testosterone levels and depression can influence each other, creating a potentially reinforcing cycle. Scientific literature demonstrates a relationship between depression and tesosterone levels but it's difficult to establish which is the causative agent due to their interconnected and bidirectional nature. This underscores the importance of comprehensive clinical evaluation and further research to unravel the nuanced connections between other mental health issues and various hormone levels.
Testosterone -> Depression: Low testosterone levels have been associated with symptoms of depression. Testosterone plays a role in mood regulation, and a deficiency may contribute to feelings of fatigue, irritability, and low mood. Additionally, Testosterone can affect neurotransmitter systems, such as serotonin and dopamine, which play crucial roles in mood regulation. Changes in these neurotransmitters may contribute to depressive symptoms.
Depression -> Testosterone: Chronic stress and elevated cortisol levels, often associated with depression, can lead to a reduction in testosterone production. High cortisol levels may interfere with the function of the hypothalamus and pituitary gland, which regulate testosterone production. Also note that depression can also lead to unhealthy lifestyle choices, such as poor diet, lack of exercise, and disrupted sleep patterns.
Please note that the reference ranges for Total Testosterone only give a broad guide, ideal levels are highly independent and best assessed through a symptom based approach, which is outlined above. In addition, the readings for women may fluctuate depending on the stage of the menstrual cycle.
Moreover, it is imperative that any recommendations be implemented under the supervision of a medical professional, commencing at a conservative modification/dose and incrementally titrating up to the recommended effective modification/dose only in the absence of any adverse symptoms or signs.