Low Testosterone (Low T)
Not all men produce enough testosterone. This can occur at any age and for a variety of reasons. When the testicles do not produce enough testosterone, we call this condition hypogonadism. Hypogonadism can be either primary (failure of the testicles to produce testosterone) or secondary (failure of the pituitary gland to signal the testicles to make testosterone). Hypogonadism can also result in less sperm production which leads to infertility. Low sperm counts will be discussed in in the section on infertility (click HERE to learn more). In this section we will focus on the low testosterone effects of hypogonadism.
Primary hypogonadism occurs when the problem with testosterone production is due to the testicles. In these men gonadotropin levels are normal or even high (trying to signal the testicles to make testosterone). The hypothalamus and pituitary are working just fine; it’s the testicles that are not functioning properly. This can occur in genetic disorders like Kleinfelter’s Syndrome (click HERE to learn more) where men are born with an extra X chromosome. It can also occur when one or both testicles have not descended into the scrotum after birth or retract into the body rather than staying in the scrotum after birth (click HERE to learn more). The warmer body temperatures can damage and inhibit the production of testosterone. Finally, infections (like mumps), some cancer treatments, or injury to the testicles can also cause tissue damage in the testicles and reduce their ability to produce enough testosterone for the male body.
Secondary hypogonadism occurs when the hypothalamus and/or pituitary gland fail to send gonadotropin hormones to the testicles to trigger them to make testosterone. A variety of disorders that affect the hypothalamus and pituitary can be causative reasons. Even severe health issues and stress can decrease the functioning of the hypothalamus, thus decreasing testosterone levels.
Finally, some conditions are linked to the testicles, pituitary, and hypothalamus. Age is perhaps the largest contributor since testosterone levels decrease as men age. Taking testosterone replacement products or pro-hormones can cause hypogonadism in the long-term since circulating testosterone levels are kept high by the medications and the pituitary has no need to produce gonadotropins. This can halt the signals sent to the testicles to make testosterone. If the testicles are not “working” they atrophy, or shrink, and become less effective at producing testosterone in the future. Other conditions like HIV/AIDS, medications, and obesity can also contribute to hypogonadism as well.
Symptoms of low testosterone can vary by age. Hypogonadism during fetal development usually involves a newborn being born with genitals that aren’t well developed or even look like female genitals (click HERE to learn more). When hypogonadism occurs in adolescence, puberty is delayed or slowed which can lead to reduced growth of the penis and testicles. Wet dreams can be less frequent or non-existent (even if the young man does not masturbate). Facial and body hair are limited, and the chest can develop a more breast-like appearance. Growth can also be affected with many hypogonadal young men growing taller than normal and have low muscle mass (tall and fairly slender).
Symptoms in adult men deal less with genital and body appearance and focus more on symptoms involving well-being and sexual function. Since hypogonadism can be caused by aging, some of these symptoms come on gradually rather than all at once. Symptoms in adult men can include the following:
Lack of energy
Decreases in muscle mass
Diminished body hair growth (some men may notice body hair thinning, especially with age)
Infertility (decreased sperm production)
Decreased libido (desire for sex)
Erectile dysfunction (especially a lack of nocturnal erections while sleeping/waking up)
Blood tests can be performed to assess testosterone levels. But these tests can be
somewhat misleading at times. Testosterone levels rise and fall throughout the day. In fact,testosterone typically peaks first thing in the morning (one of the reasons many men notice having an erection when they wake up in the morning). If a blood test is not taken in the morning, it may falsely suggest that testosterone levels are low, when in fact they are not. For men who are low in testosterone, there are two main treatment methods which your healthcare professional may recommend – nutritional/lifestyle changes and testosterone replacement.
Nutrition & Vitamins
Testosterone production requires adequate fat intake, as well as certain minerals. Some “good” fats and adequate cholesterol are essential to having enough building blocks on board for the testicles to produce testosterone. “Good” fats include olive oil, almonds, egg yolks, and even some saturated fat. Keep in mind, staying within the daily recommended allowance is a good guide as to how much fat to consume. Consuming excess fat and cholesterol can have adverse effects on your heart health – so moderation in all things is vital. The point here is that a “fat-free” diet is not ideal for testosterone production.
Vitamins and minerals are important for the testicles to produce testosterone as well. Zinc is a mineral involved in a key step of testosterone production. Zinc is found in low levels in many foods, but the food with the highest zinc content is shellfish (like oysters) and other seafood such as crab, lobster, and shrimp. When a man has low levels of zinc, testosterone production is often low. Unfortunately, zinc isn’t stored well in humans and nearly one-third of people are thought to be deficient in zinc. Furthermore, zinc is concentrated in semen, with zinc levels being 87 times higher in semen than in the blood.[i] Men who have a low dietary intake of zinc or ejaculate frequently may experience low zinc levels which can result in low testosterone levels. Taking 25-30mg of zinc per day is sufficient. Higher doses of zinc are not more effective and can actually cause some side effects such as inhibiting appropriate absorption of other minerals like copper. In addition, too much zinc can decrease sperm motility in semen. Since testosterone production occurs largely at night, taking zinc prior to bedtime can boost testosterone levels – sometimes by more than 100-200 points (ng/dl). Many men that start taking zinc at bedtime report signs of increased testosterone levels such as more energy, more muscle building ability, better sexual function, and an increase (or resumption) of nocturnal erections. Some men simply report more rigid nocturnal erections. As we’ll discuss later, rigid nocturnal erections are Nature’s way of keeping the reproductive tissues of the penis healthy in addition to facilitating the male body to have wet dreams when needed. Zinc is also necessary for the production of prostatic antibacterial factor, a substance produced by the prostate to fight bacteria and prevent infection and inflammation in the prostate.[ii] (click HERE to learn more)
Testosterone levels also rise and fall with the seasons of the year. Testosterone levels are often higher in the longer days of the year (spring and summer) than they are in the shorter days of the year (fall and winter). It is suspected that this is due to the role of vitamin D. Vitamin D is produced in the skin from exposure to sunlight. Since we spend much of our time indoors or covered in sunscreen vitamin D levels are often low. Vitamin D actually acts as a trigger in the testicles to promote testosterone production. So having adequate vitamin D on board can assist the testicles to “get going.” In addition; vitamin D can assist in strengthening bones by increasing calcium absorption so men with weaker bones can get an added benefit of bone strengthening. Vitamin D in 1,000 to 2,000u per day is sufficient to help increase vitamin D and potentially testosterone production. Higher doses of vitamin D should not be used unless prescribed by your healthcare provider.
Some men wonder about testosterone boosters they may find in supplement and nutrition shops. Overall, these products provide compounds that can be converted into testosterone by the liver. This is NOT ideal. The testicles should be producing testosterone, not the liver. Any increases in testosterone in the blood stream that doesn’t come from the testicles shuts off the pituitary hormones that signal the testicles to produce testosterone. This can cause the testicles to stop their own production of testosterone by relying on exogenous (sources outside of the body) for testosterone. This leads to shrinkage of the testicles, and in some cases, the inability of the testicles to resume normal testosterone production once these products are discontinued. The use of over-the-counter testosterone boosters is not recommended without consulting your healthcare provider. In addition, it can be very hard on the liver to convert pro-hormones to testosterone. This is yet another reason why over-the-counter pro-hormone supplements are particularly worrisome and should be avoided.
Perhaps the most widely known way to increase testosterone is to take testosterone as a medication. Testosterone is a prescription product that is available in a number of different forms. These range from injectable oil to topical gels and patches. We call these products “testosterone replacement” therapies. Just as the name implies, testosterone replacement replaces the testosterone that should be made by the testicles.
As previously stated, when a man gets testosterone from outside of the body (exogenously), the testicles typically shut down production since testosterone blood levels are high enough. This is actually a safety measure built into men to prevent over-production of testosterone.
Normally, when testosterone reaches a certain level in the blood stream, the pituitary gland stops sending LH (leutenizing hormone) to the testicles. The testicles then stop producing testosterone. When testosterone levels drop, LH levels increase to signal the testicles to make testosterone. If testosterone is being administered by injections, gels, and patches; basically if testosterone levels are “normal” or “high”; then no LH will be produced by the pituitary and the testicles will not be triggered to make testosterone. This lack of testosterone production by the testicles leads to atrophy (shrinkage). Just like muscles shrink when they aren’t worked, testicles will also shrink if they are not “working” to produce testosterone. Some men who have been on testosterone replacement for some time will have
testicles that shrink considerably, sometimes to the size of a peanut since their pituitary isn’t producing gonadotropins.
For many men, as soon as they start using testosterone replacement products, the testicles begin shutting down and eventually are not able to produce testosterone; even if the man stops taking testosterone replacement products later. So starting testosterone replacement products is often a long-term, life-long decision and not one to be taken lightly.
As stated earlier, testosterone replacement products come in many forms. There are injections that can be given every week for 2-10 weeks depending on the product. Topical gels that are applied daily are also available. However, each topical product is designed to be applied only to certain skin areas. For example, some topical products are to be applied to the upper/outer thighs, others to the torso or shoulders, and yet others in the armpits. Patches are also available; but, like gels, they are designed to be applied to certain areas. One patch is designed to be applied to the torso, upper arm, or shoulder; while another patch is designed to be applied to the upper gums inside the mouth. Applying these products to areas where they are not designed can lead to inappropriate testosterone levels since skin has different thicknesses and blood supplies on various parts of the body. There are also other testosterone products – a nasal spray, implantable pellets that slowly dissolve beneath the skin, and even oral tablets. However, oral tablets have fallen out of favor because the liver metabolizes or nearly eliminates all of the testosterone before it makes it to the blood stream which can be hard on the liver.
Testosterone replacement products used after puberty do have side effects in addition to testicular atrophy (shrinkage). These include:
Infertility as the testicles shrink in size and function.
Rage and loss of temper control. This can be more noticeable in the injections and implants that are given every few weeks rather than other products that are given daily and have more consistent levels.
Gynecomastia is a condition where increases in testosterone can lead to increases in the conversion of excess testosterone into estrogen – thus leading to a swelling of the chest into “breasts.” In men this can be painful and can also be disturbing as “pecs” become more breast-like in shape.
Benign prostatic hypertrophy is a swelling of the prostate (click HERE to learn more). Testosterone continues to cause the prostate to grow in size; and BPH symptoms, such as needing to urinate frequently or having difficulties urinating, may occur.
Chances of prostate cancer may also be increased as testosterone can signal or promote prostate cancer cells to grow and multiply.
Cardiac risks are also becoming a concern. Edema or swelling, especially in the lower legs, is a side effect that some men may notice.
Virilization (masculinizing) of girls and women that come into contact with testosterone gels or patches. This can occur when girls or women touch the skin area on a man where testosterone is applied. This can lead to body hair growth in females that is similar to men (chest and facial hair growth); as well as enlargement of the clitoris, as testosterone tries to make that tissue become more “penis-like.” Young boys who touch testosterone products, or the skin where testosterone has been applied, may start going into puberty; even if they are young children.
Because these side effects can be significant, testosterone replacement won’t be for everyone. Typically nutritional therapy with diet and vitamin supplementation rarely, if ever, leads to these side effects. The body is able to produce appropriate levels of testosterone rather than being at the mercy of the dose of testosterone replacement. Testosterone replacement should medically be reserved for men who have a condition that decreases testosterone levels, such as hypogonadism (poorly functioning testicles)and Kleinfelter Syndrome ((click HERE to learn more)). Testosterone can also be appropriately used in some boys with Delayed Puberty (click HERE to learn more). Talk to your healthcare provider if you are concerned about low testosterone and discuss what therapy (if any) is appropriate for you.
[i] Khan et. al. Int J Appl Basic Med Res, Assessment of the level of trace element zinc in seminal plasma of males and evaluation of its role in male infertility 2011 Jul-Dec; 1(2) 93-96. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3657968/ 7/22/17)
[ii] W Sawatan, et.al. Age Related Male Problem: Acute and Chronic Bacterial Prostatitis, Internal Journal of Medicine and Pharmaceutical Sciences, 4(2), Apr 2014,
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