Are you getting enough vitamin D? Vitamin D is an essential nutrient, but it can be difficult for people to know if they are getting the right amount. Some people will be able to get enough vitamin D from sunlight. Others may need to make dietary changes or take supplements. Here, we explain how to get vitamin D from sunlight, food, and supplements. Read now

Testosterone is observed in most vertebrates. Testosterone and the classical nuclear androgen receptor first appeared in gnathostomes (jawed vertebrates).[189] Agnathans (jawless vertebrates) such as lampreys do not produce testosterone but instead use androstenedione as a male sex hormone.[190] Fish make a slightly different form called 11-ketotestosterone.[191] Its counterpart in insects is ecdysone.[192] The presence of these ubiquitous steroids in a wide range of animals suggest that sex hormones have an ancient evolutionary history.[193]
Androderm / Andronate 100 / Andronate 200 / Andropatch (GlaxoSmithKline) / Andropository 200 / Andryl 200 / Bio-T-Gel (BioSante Pharmaceuticals, Inc. and Teva Pharmaceuticals USA, Inc.) / Fortigel / Intrinsa (Procter & Gamble) / Livensa (Procter & Gamble) / Nebido (Bayer) / Sustanon (Organon) / Synandrol F / Testamone 100 / Testaqua IM / Testoderm / Testoderm TTS / Testogel (Bayer) / Testolin / Testopatch (Pierre Fabre) / Testopel Pellets / Testrin-P.A / Testro AQ / Tostrelle / Tostrex / Virormone (Nordic Pharma)
Testosterone is a hormone that is secreted in both men and women. It is responsible for sex drive, as well as protein processing for muscle mass development and strength. Testosterone declines with age, illness and poor nutrition in both genders, though this change may be more marked in men. Synthetic hormone replacement therapy can cause adverse side effects. A natural way to raise the body’s testosterone levels safely include supplementing the diet with specific nutrients and physical exercise.

When your testosterone levels go up, so does your libido. Unfortunately, the inverse is not true — your libido levels can go up without your testosterone levels also going up. And that’s how most supposed T-boosters “work”: they make you feel ornery, leading you to think that your T levels are appreciably higher, when they actually aren’t. In rare cases, supplementation will result in a 20% testosterone increase. This kind of improvement may sound impressive, but is irrelevant for practical purposes.
Puberty occurs when there is an “awakening” of the hypothalamic-pituitary axis. The hypothalamus increases its secretion of gonadotropin releasing hormone (GnRH) which in turn stimulates the release of luteinizing hormone (LH) and follicle stimulating hormone (FSH). This leads to a significant increase in the production of testicular testosterone and the induction of the well-known secondary sex characteristics associated with puberty: growth spurt, increased libido, increased erectile function, acne, increased body hair, increased muscle mass, deepening of the voice, spermatogenesis, gynecomastia (usually transient).
As already indicated previously, testosterone levels, particularly bioavailable testosterone, fall with advancing age. This decline in testosterone availability may start to occur early in the forth decade but it usually becomes clinically manifest in the 50s and 60s. Although there is continuing debate about the best way to diagnose hypogonadism in the aging male, there appears to be a general consensus that symptomatic men with reduced levels of testosterone should be given a trial of testosterone therapy if there is no contraindication to do so (Bain et al 2007).

There are several supplements on the market claiming to be natural testosterone boosters. I get these sorts of things in the mail all time. The companies that produce these products claim that the herbs (typically stinging nettle and tribulus) in their pills increase free testosterone by reducing SHBG. They also throw in some B vitamins for “increased energy and vitality.”
The steroid hormone known as dehydroepiandrosterone, DHEA, plays an important role in sexual behavior, mental health and muscle growth. Your body uses this hormone to make sex steroids. Thus, taking a DHEA supplement should increase your circulating testosterone. A 2018 paper in the International Journal of Sports Medicine explored this possibility in athletic women.
Nutritional developers formulated Nugenix® with Testofen®, a key natural ingredient to help boost “free” testosterone along with resistance training. This key ingredient is carefully extracted from the fenugreek plant. A Testofen® study in Irvine, California indicated positive free testosterone-related results. Nugenix also includes L-Citrulline Malate, Tribulus, Zinc, plus Vitamins B6 and B12 to help promote overall health and performance.*

Your body’s circadian rhythm essentially resets itself every night and releases chemicals like cortisol, which contribute to the overall hormone balance that can prevent low T-levels. I have even heard one endocrinologist claim that one hour of sleep between 10 p.m. and 2 a.m. has the same healing effects on your body as two hours of sleep before or after this timeslot!
While it would be nice to buy a testosterone pill from the local supplement store and have your testosterone levels go up, such a magic pill does not exist. As you can see from the above rundown, while a few supplements may be somewhat effective if your T levels are already low, none will significantly raise your testosterone above a baseline level. Thus, the basics of keeping your T levels high remain pretty simple:
A: Testosterone production declines naturally with age. Low testosterone, or testosterone deficiency (TD), may result from disease or damage to the hypothalamus, pituitary gland, or testicles that inhibits hormone secretion and testosterone production. Treatment involves hormone replacement therapy. The method of delivery is determined by age and duration of deficiency. Oral testosterone, Testred (methyltestosterone), is associated with liver toxicity and liver tumors and so is prescribed sparingly. Transdermal delivery with a testosterone patch is becoming the most common method of treatment for testosterone deficiency in adults. A patch is worn, either on the scrotum or elsewhere on the body, and testosterone is released through the skin at controlled intervals. Patches are typically worn for 12 or 24 hours and can be worn during exercise, bathing, and strenuous activity. Two transdermal patches that are available are Androderm (nonscrotal) and Testoderm (scrotal). The Androderm patch is applied to the abdomen, lower back, thigh, or upper arm and should be applied at the same time every evening between 8 p.m. and midnight. If the patch falls off before noon, replace it with a fresh patch until it is time to reapply a new patch that evening. If the patch falls off after noon, do not replace it until you reapply a new patch that evening. The most common side effects associated with transdermal patch therapy include itching, discomfort, and irritation at the site of application. Some men may experience fluid retention, acne, and temporary abnormal breast development (gynecosmastia). AndroGel and Testim are transdermal gels that are applied once daily to the clean dry skin of the upper arms or abdomen. When used properly, these gels deliver testosterone for 24 hours. The gel must be allowed to dry on the skin before dressing and must be applied at least 6 hours before showering or swimming. Gels cannot be applied to the genitals. AndroGel is available in a metered-dose pump, which allows physicians to adjust the dosage of the medication. Side effects of transdermal gels include adverse reactions at the site of application, acne, headache, and hair loss (alopecia). For more specific information on treatments for low testosterone, consult with your doctor or pharmacist for guidance based on current health condition. Kimberly Hotz, PharmD
A: If a health insurance company is providing coverage for a medication, including testosterone replacement therapy, they determine the final cost of the product. Costs will vary from one health insurance plan to another. To determine the costs of the testosterone replacement options, the health insurance plan should be contacted. There are various options for testosterone replacement therapy including gels, injections, patches, and tablets that dissolve under the lip. All of the formulations can be effective and each has advantages and disadvantages. The most appropriate testosterone replacement therapy depends on a variety of factors, including cost, patient preference, and tolerability. Testosterone replacement gels, such as AndroGel and Testim, are very effective and easy to administer. AndroGel and Testim can be easily applied to the skin once daily. However, the gels can be irritating to the skin and AndroGel and Testim are typically quite expensive. Testosterone replacement injections, such as Depo-Testosterone (testosterone cypionate) and Delatestryl (testosterone enanthate), are usually inexpensive. The injections are given only once every one to two weeks. The major disadvantage with injectable testosterone is that testosterone levels may be difficult to control. Levels may be too high after an injection and too low before the following injection. A testosterone replacement patch, such as Androderm, is applied every night and left on for 24 hours. Androderm can be applied to the arm, back or stomach, in an area without too much hair. Androderm can cause irritation of the skin. A testosterone tablet, Striant, is placed under the upper lip against the gums and replaced every 12 hours. Striant molds to the upper gum so that eating and drinking can occur normally. The testosterone tablet can irritate the gums and cause a bitter taste and toothache. People with low testosterone should work with their doctor or healthcare provider to find a safe, effective, and affordable testosterone replacement option for them. For more specific information, consult with your doctor or pharmacist for guidance based on your health status and current medications, particularly before taking any action. Derek Dore, PharmD
ZMA (unnecessary). So when I researched how to increase testosterone, a supplement called ZMA kept popping up. It’s a blend of zinc, magnesium, and vitamin B6. The purported benefits of ZMA include better and deeper sleep which indirectly is supposed to increase testosterone. Zinc and magnesium are necessary minerals in testosterone production, so a mega-dose should be useful, right? Well, no. I bought some and took it during the duration of experiment. I should have done some more research before I made the purchase. While one study in 1998 showed increased strength among athletes taking ZMA, two recent studies (study 1, study 2) have shown that it has absolutely no effect on total or free testosterone levels. Crap. My advice, unless you have a zinc and magnesium deficiency, no need to waste your money on this.
Testosterone treatment is unequivocally needed in classical hypogonadism for reasons discussed in subsequent subsections. In classical hypogonadism, testosterone production is usually clearly below the lower limit of normal and patients are highly symptomatic; the various symptoms are easily related to the deficiencies in various bodily systems where testosterone action is important. Symptoms of testosterone deficiency are listed in Table 2. A few prominent causes of classical hypogonadism are listed in Table 3.

The finding of hypogonadism in diabetic men is not just a scientific curiosity, it may have practical management implications. Kapoor and colleagues (2006) undertook a placebo-controlled double blind study to determine the effect of testosterone therapy on insulin resistance and glycemic control in hypogonadal men with type 2 diabetes. They found that men treated with testosterone had reductions in glycated hemoglobin insulin resistance, fasting blood sugar, waist circumference, waist/hip ratio and total cholesterol.

Testosterone boosters are a class of herbal supplements aimed at naturally increasing your testosterone levels. Usually, they contain micronutrients that men are commonly deficient in, such as zinc, and which have been connected in research to healthy testosterone levels. They also may contain adaptogens, which are a class of supplement that are thought to help the body adapt to stress, or ingredients which have been connected to improved sleep. Sleep restriction has been shown to reduce testosterone in healthy young men, and as Chris Lockwood, Ph.D., notes, disturbed sleep is a common symptom of low T-levels.[1]
Why bother with such common micronutrients? Because it's not uncommon for athletes to suffer from zinc and magnesium deficiencies, partly due to inadequate replenishing of levels after intense bouts of exercise. Deficiencies in these key minerals can lead to a poor anabolic hormone profile, impaired immune function, and increased cortisol, ultimately leading to decreases in strength and performance.[6]

The diagnosis of late-onset hypogonadism requires the combination of low serum testosterone levels with symptoms of hypogonadism. Questionnaires are available which check for the symptoms of hypogonadism. These have been validated for the assessment of aging patients with hypogonadism (Morley et al 2000; Moore et al 2004) but have a low specificity. In view of the overlap in symptoms between hypogonadism, aging and other medical conditions it is wise to use a formal method of symptom assessment which can be used to monitor the effects of testosterone replacement.


Preissner S, Kroll K, Dunkel M, Senger C, Goldsobel G, Kuzman D, Guenther S, Winnenburg R, Schroeder M, Preissner R: SuperCYP: a comprehensive database on Cytochrome P450 enzymes including a tool for analysis of CYP-drug interactions. Nucleic Acids Res. 2010 Jan;38(Database issue):D237-43. doi: 10.1093/nar/gkp970. Epub 2009 Nov 24. [PubMed:19934256]
Testosterone is used as a medication for the treatment of males with too little or no natural testosterone production, certain forms of breast cancer,[10] and gender dysphoria in transgender men. This is known as hormone replacement therapy (HRT) or testosterone replacement therapy (TRT), which maintains serum testosterone levels in the normal range. Decline of testosterone production with age has led to interest in androgen replacement therapy.[105] It is unclear if the use of testosterone for low levels due to aging is beneficial or harmful.[106]

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Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5α-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5α-reductase. DHT binds to the same androgen receptor even more strongly than testosterone, so that its androgenic potency is about 5 times that of T.[114] The T-receptor or DHT-receptor complex undergoes a structural change that allows it to move into the cell nucleus and bind directly to specific nucleotide sequences of the chromosomal DNA. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects.
“I did a lot of research on Andro400 before I ordered it because I've tried other products in the past and they haven't worked. But with this I could not believe the difference within, literally within a month. I'm 62 years old and since I started taking it I have lost 37 lbs. And I have more energy than I've had in 20 years. It's still coming off, but it's coming off slower now. It was the belly fat. I could get weight off but I could never get the tummy off, and now the tummy's coming off. Libido -- everything's better all the way around.“
The production of the stress hormone cortisol blocks the production and effects of testosterone. From a biological perspective, cortisol increases your “fight or flight” response, thereby lowering testosterone-associated functions such as mating, competing, and aggression. Chronic stress can take a toll on testosterone production, as well as your overall health. Therefore, stress management is equally important to a healthy diet and regular exercise. Tools you can use to stay stress-free include prayer, meditation, laughter, and yoga. Relaxation skills, such as deep breathing and visualization, can also promote your emotional health.
It may also become a treatment for anemia, bone density and strength problems. In a 2017 study published in the journal of the American Medical Association (JAMA), testosterone treatments corrected anemia in older men with low testosterone levels better than a placebo. Another 2017 study published in JAMA found that older men with low testosterone had increased bone strength and density after treatment when compared with a placebo. 
The testicles produce an enzyme called 11ßHSD-1 which protects your testosterone molecules from the effects cortisol.  During times of prolonged stress and chronically elevated cortisol, there simply is too much cortisol for 11ßHSD-1 to handle.  This results in testosterone molecules being destroyed inside the gonads before they even enter the bloodstream (8, 9).
Testosterone is significantly correlated with aggression and competitive behaviour and is directly facilitated by the latter. There are two theories on the role of testosterone in aggression and competition.[77] The first one is the challenge hypothesis which states that testosterone would increase during puberty thus facilitating reproductive and competitive behaviour which would include aggression.[77] Thus it is the challenge of competition among males of the species that facilitates aggression and violence.[77] Studies conducted have found direct correlation between testosterone and dominance especially among the most violent criminals in prison who had the highest testosterone levels.[77] The same research also found fathers (those outside competitive environments) had the lowest testosterone levels compared to other males.[77]

Intracoronary artery infusion of testosterone causes significant coronary artery dilatation and not constriction as previously thought (Webb et al 1999). When degree of coronary obstruction is assessed by angiography, there is a direct relationship between degree of coronary artery narrowing and reduced testosterone levels (Phillips et al 1994). Men with low testosterone levels have been observed to have: premature atherosclerosis, increased visceral adipose tissue, hyperinsulinemia, and other risk factors for myocardial infarction (Phillips 2005). Insulin resistance has been shown to be associated with a decrease in Leydig cell secretion of testosterone (Pitteloud et al 2005). Muller and colleagues suggest that low endogenous total testosterone and SHBG levels increase the risk of metabolic syndrome in aging and aged men. They demonstrated that low levels of testosterone are related to lower insulin sensitivity and higher fasting insulin levels (Muller et al 2005). These authors speculate that testosterone might play a protective role in the development of metabolic syndrome, insulin resistance, diabetes mellitus and cardiovascular disease in aging men.


A loophole in FDA regulations allows pharmaceutical marketers to urge men to talk to their doctors if they have certain "possible signs" of testosterone deficiency. "Virtually everybody asks about this now because the direct-to-consumer marketing is so aggressive," says Dr. Michael O'Leary, a urologist at Harvard-affiliated Brigham and Women's Hospital. "Tons of men who would never have asked me about it before started to do so when they saw ads that say 'Do you feel tired?'"
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