Low Testosterone

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    Mike Murray, Nick Milazzo

    Fact-checked

    by:

    Morgan Pfiffner, Igor Deoli
    Last Updated: August 14, 2023

    Low testosterone results from a problem in the testicles or the brain and can cause low libido, muscle loss, and/or depressed mood. It is primarily treated with testosterone replacement therapy.

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    Low Testosterone falls under the Men’s Health and Healthy Aging & Longevity categories.

    98 references on this page
    2,165 participants in 27 trials

    What is low testosterone?

    Testosterone is the best-known androgen (i.e., male sex hormone). It is secreted by the testicles and is responsible for the development and maintenance of secondary male characteristics (e.g., increased body and facial hair, enlarged larynx, deep voice, muscularity). Low testosterone (i.e., hypogonadism) results from the failure of the testicles (i.e., the gonads) to produce normal levels of testosterone due to a problem within the hypothalamic-pituitary-testicular (HPT) axis.[1]

    What are the main signs and symptoms of low testosterone?

    • Low sex drive
    • Erectile dysfunction (i.e., the inability to get or keep an erection)
    • Low sperm count
    • Reduced muscle mass and strength and increased fat mass
    • Low bone density (i.e., osteoporosis)
    • Loss of body hair
    • Gynaecomastia (i.e., enlargement of breast tissue)
    • Sleep disturbances
    • Reduced energy, depressed mood, and trouble concentrating

    How is low testosterone diagnosed?

    Testosterone levels are assessed using a blood test. The cutoff for low testosterone differs between organizations, but most define it as a total testosterone level of <231–275 ng/dL.[2] Testosterone levels should be assessed early in the morning (between 7–11 a.m.) when peak levels occur, and in a fasted state. Two separate low testosterone measurements (preferably four weeks apart) along with clinical signs and symptoms of low testosterone are needed to be diagnosed with low testosterone.

    What are the different metrics used to assess testosterone levels?

    What are some of the main medical treatments for low testosterone?

    Testosterone replacement therapy (TRT) is the primary treatment option for low testosterone and can be given as an oral pill, buccal tablet (which dissolves in the mouth), injection, nasal gel, topical gel, transdermal patch (worn on the skin), or implant.[1] TRT appears to be safe,[3] although there is limited data on long-term safety.

    Each form of administration can cause unique adverse effects, but in general, TRT may cause erythrocytosis (as indicated by a hematocrit level > 54%), dyslipidemia, acne, oily skin, reduced sperm production, and/or growth of metastatic prostate cancer.[1][4] Additionally, TRT is contraindicated for certain populations (e.g., people with a recent history of heart attack or stroke, heart failure, or prostate cancer).[1]

    Have any supplements been studied for low testosterone?

    A long list of supplements are marketed as testosterone boosters, but there is scant evidence to suggest that any of them affect testosterone levels.[5][6] Some of the more popular options include saw-palmetto, ashwagandha, tribulus-terrestris, fenugreek, d-aspartic-acid, maca, horny-goat-weed, and boron.

    Supplementing with certain nutrients such as vitamin D, zinc, and magnesium can slightly increase testosterone levels if dietary intake and serum levels are inadequate.[7]

    Can testosterone boosters bring my testosterone back to normal?

    Can creatine increase your testosterone levels?

    Does ashwagandha increase testosterone?

    How could diet affect low testosterone?

    In many men low testosterone is caused by reversible conditions, such as excess body fat and chronic disease (e.g., type-2-diabetes, metabolic-syndrome). Consequently, a hypocaloric diet is very effective for increasing testosterone levels in this population,[8] whereas a hypocaloric diet seems to reduce testosterone levels in lean men.[9][10]

    In addition, it’s worth paying attention to dietary fat levels, because limited evidence suggests that low-fat diets (≤25% of energy intake) decrease testosterone levels compared to higher-fat diets (about 40% of energy intake).[11]

    Are there any other treatments for low testosterone?

    Exercise — whether it’s aerobic exercise, high-intensity interval training, or resistance training — increases testosterone levels,[12] especially when it’s included as part of a lifestyle intervention to reduce body weight.[13] Exercise may also improve the effectiveness of TRT.[14] Bariatric surgery is another effective method for increasing testosterone levels in men with obesity.[15]

    Will exercise increase my testosterone levels?

    How does resistance training affect testosterone levels?

    What causes low testosterone?

    The cause of low testosterone is classified as either primary or secondary and further categorized as functional or organic. Primary hypogonadism originates from a problem in the testicles, while secondary hypogonadism indicates a problem in the hypothalamus or the pituitary gland, which are the parts of the brain that signal the testicles to produce testosterone.[1]

    Functional hypogonadism is caused by factors that suppress testosterone levels (e.g., medications, obesity, type 2 diabetes, aging, excessive exercise, malnutrition) but are potentially reversible, while organic hypogonadism is caused by a congenital, structural, or destructive condition (e.g., Klinefelter syndrome, Kallmann syndrome, hemochromatosis, inflammatory disease, injury to the testicles, traumatic brain injury, chemotherapy or radiation) that results in largely irreversible hypothalamic, pituitary, or testicular dysfunction.[1]

    Will gaining fat decrease my testosterone levels?

    How does aging affect testosterone levels?

    Which drugs decrease testosterone levels?

    Does ejaculation affect testosterone levels?

    Examine Database: Low Testosterone

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    Frequently asked questions

    What is low testosterone?

    Testosterone is the best-known androgen (i.e., male sex hormone). It is secreted by the testicles and is responsible for the development and maintenance of secondary male characteristics (e.g., increased body and facial hair, enlarged larynx, deep voice, muscularity). Low testosterone (i.e., hypogonadism) results from the failure of the testicles (i.e., the gonads) to produce normal levels of testosterone due to a problem within the hypothalamic-pituitary-testicular (HPT) axis.[1]

    What are the main signs and symptoms of low testosterone?
    • Low sex drive
    • Erectile dysfunction (i.e., the inability to get or keep an erection)
    • Low sperm count
    • Reduced muscle mass and strength and increased fat mass
    • Low bone density (i.e., osteoporosis)
    • Loss of body hair
    • Gynaecomastia (i.e., enlargement of breast tissue)
    • Sleep disturbances
    • Reduced energy, depressed mood, and trouble concentrating
    How is low testosterone diagnosed?

    Testosterone levels are assessed using a blood test. The cutoff for low testosterone differs between organizations, but most define it as a total testosterone level of <231–275 ng/dL.[2] Testosterone levels should be assessed early in the morning (between 7–11 a.m.) when peak levels occur, and in a fasted state. Two separate low testosterone measurements (preferably four weeks apart) along with clinical signs and symptoms of low testosterone are needed to be diagnosed with low testosterone.

    What are the different metrics used to assess testosterone levels?

    Total testosterone refers to the sum of the concentrations of protein-bound and unbound testosterone in the circulation and can be broken down into three categories:[28]

    • Tightly bound testosterone: About two-thirds of testosterone in the blood is bound to sex hormone binding globulin. It is not readily available for use by the body.
    • Loosely bound testosterone: About one-third of testosterone in the blood is weakly bound to albumin. Once the bond is broken, the testosterone circulates as free testosterone in the body.
    • Free testosterone: A small percentage of testosterone in the blood floats around freely. The body can readily use it, and the enzyme 5-alpha-reductase can convert it to DHT. The term bioavailable testosterone refers to the sum of loosely bound and free testosterone.

    Assessing testosterone levels

    image
    What are some of the main medical treatments for low testosterone?

    Testosterone replacement therapy (TRT) is the primary treatment option for low testosterone and can be given as an oral pill, buccal tablet (which dissolves in the mouth), injection, nasal gel, topical gel, transdermal patch (worn on the skin), or implant.[1] TRT appears to be safe,[3] although there is limited data on long-term safety.

    Each form of administration can cause unique adverse effects, but in general, TRT may cause erythrocytosis (as indicated by a hematocrit level > 54%), dyslipidemia, acne, oily skin, reduced sperm production, and/or growth of metastatic prostate cancer.[1][4] Additionally, TRT is contraindicated for certain populations (e.g., people with a recent history of heart attack or stroke, heart failure, or prostate cancer).[1]

    Have any supplements been studied for low testosterone?

    A long list of supplements are marketed as testosterone boosters, but there is scant evidence to suggest that any of them affect testosterone levels.[5][6] Some of the more popular options include saw-palmetto, ashwagandha, tribulus-terrestris, fenugreek, d-aspartic-acid, maca, horny-goat-weed, and boron.

    Supplementing with certain nutrients such as vitamin D, zinc, and magnesium can slightly increase testosterone levels if dietary intake and serum levels are inadequate.[7]

    Can testosterone boosters bring my testosterone back to normal?

    DHEA, vitamin D, magnesium, and zinc have been seen to raise low testosterone levels. Few other supplements seem to help at all.

    A few trials support the use of coleus-forskohlii, but its numerous potential adverse effects make it a risky proposition, especially for older people.

    You might also have heard of d-aspartic-acid, but its promising initial trials were followed by several others that found that it didn’t increase testosterone.

    Some other supplements, such as ginger and Eurycoma longifolia, might support testosterone levels only in infertile men (or in men with testicular damage).

    Many other herbs, such as horny-goat-weed, have not even been studied in humans yet.

    Finally, keep in mind that a supplement can benefit libido (as do maca and, according to a small number of studies, tribulus-terrestris), mood, or energy levels, yet not affect testosterone.

    Can creatine increase your testosterone levels?
    Quick answer:

    The evidence is mixed, but the preponderance of the evidence suggests that it’s unlikely that creatine will increase your testosterone levels.

    The evidence is mixed, but the preponderance of the evidence suggests that it’s unlikely that creatine will increase your testosterone levels.

    Three randomized controlled trials conducted in healthy young men reported that supplementing with creatine for 1–3 weeks produced small increases in the levels of testosterone or dihydrotestosterone (DHT; a highly active androgen converted from testosterone).[29][30][31] One of the 3 trials looked at the effect of creatine loading (25 grams/day for 1 week) followed by a maintenance phase (5 grams/day for 2 weeks) on testosterone and DHT in 20 young, healthy rugby players. Although no effect on testosterone was found, creatine increased the levels of DHT by 12 nanograms of DHT per deciliter of blood (ng/dL).[29] The other 2 trials found that supplementation with creatine for 1 week in healthy, active young men increased the concentrations of testosterone by 57 ng/dL and 150 ng/dL.[30][31]

    Conversely, 10 other trials (involving a total of 218 participants) looking at the effect of supplemental creatine at daily doses of 3–25 grams on testosterone levels for up to 12 weeks have found no statistically significant effect.[32][33][34][29][35][36][37][38][39][40] The participants in the majority of these trials were healthy, active young men. With regard to the form of creatine used, 9 trials administered creatine monohydrate, whereas 1 trial administered creatine malate. It’s worth noting that no trials have looked at the effect of creatine on testosterone in men with abnormally low testosterone levels.

    image

    Taken together, the available evidence suggests that supplementing with creatine is unlikely to increase testosterone levels, at least in young healthy men whose testosterone levels are within the normal range.

    Does ashwagandha increase testosterone?
    Quick answer:

    There is a bit of evidence that shows Ashwagandha increases testosterone, but it is not convincing.

    What is Ashwagandha?

    Ashwagandha is a traditional Indian medicine (Ayurveda) that is known to be associated with male virility and vitality; a common supplement to recommend to men that are feeling past their prime and a traditional medicine with a surprisingly large amount of evidence overall. It does seem to have some anti-stress effects due to having the properties of an adaptogen.

    Among the adaptogens and traditional medicine, however, ashwagandha is one of the few associated with masculinity. Since anything that can be named a testosterone booster gets praise faster than it gets research, many people are wondering whether ashwagandha can increase testosterone or whether it is overhyped.

    What does it do?

    When it comes to the topic of testosterone, the first study to find an effect was one in male rats where an increase was seen.[41] When later tested in men suffering from some degree of infertility, improvements in sperm quality came alongside subtle boosts in testosterone around the range of 14-40%[42] or 10-22%[43].

    While a promising supplement for fertility, it should be stated that supplements that can provide antioxidant support to the testicles are at times associated with an increase in testosterone in infertile but not otherwise fertile men (Vitamin E and CoQ10, for example). Other profertility drugs, such as D-Aspartic acid, are commonly confused with testosterone boosting supplements when the benefits seen in infertile men are erroneously extrapolated.

    However, despite all that, at least one study has found a mild increase in testosterone in otherwise healthy men subject to weight training by 15%.[44] It is not likely that a 15% increase in testosterone will result in major changes in muscularity, but an earnest increase in testosterone in healthy young men by a dietary supplement is quite rare.

    While it is more likely a profertility agent, we cannot deny a possibility that ashwagandha could increase testosterone. However, evidence at this time is quite limited.

    How could diet affect low testosterone?

    In many men low testosterone is caused by reversible conditions, such as excess body fat and chronic disease (e.g., type-2-diabetes, metabolic-syndrome). Consequently, a hypocaloric diet is very effective for increasing testosterone levels in this population,[8] whereas a hypocaloric diet seems to reduce testosterone levels in lean men.[9][10]

    In addition, it’s worth paying attention to dietary fat levels, because limited evidence suggests that low-fat diets (≤25% of energy intake) decrease testosterone levels compared to higher-fat diets (about 40% of energy intake).[11]

    Are there any other treatments for low testosterone?

    Exercise — whether it’s aerobic exercise, high-intensity interval training, or resistance training — increases testosterone levels,[12] especially when it’s included as part of a lifestyle intervention to reduce body weight.[13] Exercise may also improve the effectiveness of TRT.[14] Bariatric surgery is another effective method for increasing testosterone levels in men with obesity.[15]

    Will exercise increase my testosterone levels?

    Resistance training can temporarily raise testosterone levels for 15–30 minutes post-exercise.[16][17] More importantly, it can benefit testosterone production in the long run by improving body composition and reducing insulin resistance.[16]

    Overtraining, however, is counterproductive. Prolonged endurance exercise especially can cause your testosterone to drop.[18][19] Ensuring adequate recovery time will help you receive the full benefits of physical activity.

    How does resistance training affect testosterone levels?

    In general, serum testosterone rises immediately following resistance training in men, but returns to baseline, or even below baseline, after about 30 minutes.[20] In women, some studies have also found short-term increases in serum testosterone, but others haven’t, so the results are more equivocal.

    What causes low testosterone?

    The cause of low testosterone is classified as either primary or secondary and further categorized as functional or organic. Primary hypogonadism originates from a problem in the testicles, while secondary hypogonadism indicates a problem in the hypothalamus or the pituitary gland, which are the parts of the brain that signal the testicles to produce testosterone.[1]

    Functional hypogonadism is caused by factors that suppress testosterone levels (e.g., medications, obesity, type 2 diabetes, aging, excessive exercise, malnutrition) but are potentially reversible, while organic hypogonadism is caused by a congenital, structural, or destructive condition (e.g., Klinefelter syndrome, Kallmann syndrome, hemochromatosis, inflammatory disease, injury to the testicles, traumatic brain injury, chemotherapy or radiation) that results in largely irreversible hypothalamic, pituitary, or testicular dysfunction.[1]

    Will gaining fat decrease my testosterone levels?

    Fat gain and the associated increase in chronic disease risk, such as cardiovascular disease and type 2 diabetes, are strongly linked to decreases in testosterone, particularly in middle-aged and older men.[21][22][23] If you gain weight (as fat), your testosterone production drops. Fortunately, if you lose weight, your testosterone production can climb back up.

    Effect of weight loss on testosterone levels

    image

    Reference: Grossmann and Matsumoto. J Clin Endocrinol Metab. 2017.[8]

    A meta-analysis of 24 RCTs looked at weight loss caused by diet or bariatric surgery.[15] In the diet studies, the average 9.8% weight loss was linked to a testosterone increase of 2.9 nmol/L (84 ng/dL). In the bariatric-surgery studies, the average 32% weight loss was linked to a testosterone increase of 8.7 nmol/L (251 ng/dL). You need not lose huge amounts of weight to see a bump in testosterone levels, either: a 5% loss in weight may increase total testosterone by 2 nmol/L (58 ng/dL).[24]

    How does aging affect testosterone levels?

    Middle-aged[25] and older[26] men see their total testosterone levels decrease by 0.4% to 1.6% per year, many of whom had lower-than-average levels even in their 30s.[27] Bioavailable testosterone decreases by about 2–3% a year.[25]

    Those numbers can be pretty misleading, though. Men approaching middle age tend to exercise a lot less and eat a lot worse. So it’s hard to say what a “natural” decline in testosterone looks like on a population-wide basis.

    It’s kind of like saying muscle mass decreases 1–2% a year once you hit middle age. That decrease can have a lot to do with more time spent on work and family and less time spent trying to get ripped.

    Which drugs decrease testosterone levels?

    Several drugs and drug classes may decrease testosterone levels. If you are on any of the medications below and are concerned about your T levels, consult your physician. Do not stop the treatment without professional medical input.

    • Antiandrogens (e.g., cyproterone, bicalutamide, flutamide, spironolactone)
    • Chemotherapy (e.g., alkylating agents)
    • Chronic anabolic steroid use (particularly when high doses are used)
    • Glucocorticoids
    • Ketoconazole
    • Luteinizing hormone-releasing hormone agonists (aka LHRH analogs or GnRH agonists)
    • Opioids
    • Radiation therapy (total body or pelvis in particular)
    • Selective serotonin reuptake inhibitors (SSRIs)
    • Suramin
    Does ejaculation affect testosterone levels?

    What does male orgasm result in, biochemically?

    Higher serum testosterone levels are seen during abstinence (3 weeks in cited study).[45] Non-significant Luteinizing Hormone increases have also been noted.[45] The difference between abstinence and non-abstinence appears to be about 0.5ng/ml when averaged out.[45]

    Although higher testosterone levels are seen with abstinence,[46] orgasm does not acutely affect testosterone levels in the blood.[45] Although there is not much evidence for the spike in testosterone during abstinence, there does not appear to be counter evidence at the moment; it is an understudied topic.

    Orgasm can cause a significant spike in prolactin levels (approximately 10 to 15ng/ml) immediately after and upwards to 10-20 minutes later, at which it starts to decline.[45][47] This spike is dependent on ejaculation, and does not occur under non-orgasmic arousal.[48] This spike may serve to suppress further sexual desires.[49][50]

    Various cardiovascular parameters, such as heart rate and catecholamine (adrenaline, noradrenaline) levels are increased during sex/masturbation and orgasm.[47] Some measure of increase is seen during arousal.[48]

    Other various markers, such as Vasopressin and Follicle-Stimulating Hormone (FSH) remain unchanged.[48]

    Biochemical markers do not differ significantly when comparing orgasm after abstinence and orgasm without abstinence.[45] Slight increases were seen in heart rate and catecholamine (adrenaline) levels, but may be due to self-reported higher arousal on average.

    How is testosterone related to orgasm?

    Testosterone has minimal interactions with orgasm, but is seen as a positive regulator of sexual desire or libido alongside dopamine.[51][52] Agents that increase dopamine levels or act like dopamine can increase frequency of erections and subjective sexual arousal.[53][54] Prolactin is the opposite here, and is a negative regulator of sexual appetite.

    The actual ejaculatory process and erection process is mediated by serotonin and Nitric Oxide, as well as various mechanical contractions in the pelvic and penile region.[51] Drugs or supplements that interfere with serotonin reuptake (such as SSRIs) can reduce the orgasm response, and may be useful in treating premature ejaculation.[55][56]

    Dopamine is reduced temporarily as prolactin rises, as the two can be seen as antagonistic of each other. Levels shortly normalize.[57] The post-orgasm 'orgasmic state' of euphoria is mediated by prolactin and mimicked by ecstasy.[58]

    Ejaculation does not impact your testosterone levels.

    Update History

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    References

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