Testosterone (T) - the hormone with all the hype. Who wouldn’t want more of something that improves sexual function, performance, energy, muscle strength and mass? For centuries men have wanted more and now women are wanting more too (no, it’s not just a “male” hormone). As a Naturopathic Doctor, I see and support people who want to feel better or more ‘optimal’ every day - kudos to those being curious and taking control of their health. So, let’s see if you should be testing your hormone levels, if it is testosterone that you need to be optimizing, and if so, how you can boost testosterone to feel like a better, faster, stronger human.

A Little Background
Testosterone is falsely known to be a “male” hormone because of its role in the development of male sex characteristics (e.g., formation of the penis and scrotum, a deepening of the voice, and growth of facial hair) and simply because men have more of it (about 20 times more). Women, however, also require testosterone for breast, bone, vaginal, menstrual and reproductive health, as well as muscle mass and strength. Women do not produce male sex characteristics because the majority of the testosterone is converted to estrogen. Males primarily produce testosterone in the testes (95%) and small amounts in the adrenals. Women produce testosterone in the ovaries (25-35%), adrenal glands (25%), and peripheral tissues such as fat and skin cells. While levels vary, men typically have serum testosterone levels of 270-1070 ng/dL while normal ranges for women are considered to be 15-70 ng/dL. Men’s testosterone levels are more dependent on time of day (i.e., highest in the morning), while women’s testosterone levels are mostly dependant on time of month (i.e., peaking mid-menstrual cycle around ovulation). Interestingly enough, women’s energy, confidence, and libido also typically peak around ovulation making it a great time for presentations, dating, and social events. This makes sense from both a reproductive standpoint (to successfully reproduce we need to have sex around ovulation) and physiological standpoint (ovulation is a “higher hormone phase” which naturally feeds our energy). What about those who are no longer menstruating or are taking an oral contraceptive pill? The monthly “testosterone” peak is disrupted (i.e., no longer occurring) and testosterone levels do appear to be lower overall. However, it doesn’t mean these women have NO testosterone nor does it mean they can’t have a healthy sex life, extravagant energy, or muscular gains. In fact, some of the most muscular girls I know are on birth control. Hmmm, could this mean lifestyle, daily habits (and well … genetics) play a role?

The Benefits of Testosterone

• Increases lean muscle mass, strength and performance (“makes exercise feel good”)

• Strengthens bones (i.e., protective against osteoporosis and fractures)

• Improves metabolic health (e.g., decreases blood pressure, fat mass, blood sugar levels by reducing fasting insulin and HgA1c in people with pre-diabetes)

• Supports well-being (e.g., energy, libido, mood, cognition, attentiveness)

• Supports sexual and reproductive function

Do you have symptoms of low testosterone?
The most common symptoms of low testosterone are (1) low libido and/or sexual dysfunction; (2) reduced muscle mass; and (3) absent/decreased morning erections (in males, of course). However, low testosterone can also present as:

• Apathy (lack of interest, enthusiasm, or concern)

• Feeling ‘burned out’; low stamina; fatigue

• Increased body or belly fat

• Low mood; depression; irritability

• Memory problems; brain fog; poor concentration

• Bone loss; osteoporosis

• Urinary problems such as incontinence, urgency and poor retention

• In women - vaginal dryness, decreased sexual sensation, painful intercourse

• In men - erectile dysfunction, low sperm count, smaller testicles

Causes of Low Testosterone
Why is your testosterone low in the first place? It’s important to determine the cause in order to find the most suitable treatment (i.e., do you need testosterone replacement therapy or do you just need more sleep, better nutrition, and more recovery time). Causes of low testosterone include:

• Advancing age (highest levels in teens and twenties)

• Hormone imbalance (e.g., high estrogen, high cortisol)

• Nutrient deficiency (e.g., zinc, vitamin D, vitamin A, protein)

• Medical conditions (e.g., cardiovascular disease, diabetes, hemochromatosis, inflammatory conditions such as sarcoidosis, liver disease, sleep apnea)

• Medications (e.g., anabolic steroids, birth control pill, opioids, anti-hypertensives)

• Physical and mental stress (high cortisol)

• Surgery with ovaries removed

• Trauma (e.g., head injury, testicular injury)

Testing for Low Testosterone
Testing can go a long way when determining the cause of your symptoms (fatigue and low libido can be caused by other things than low testosterone). Not only can it determine ‘if’ you’re low in testosterone but it can give clues to ‘why’ you’re low in testosterone. Here’s what I usually suggest for testing:

Baseline Testing
Upon initial assessment I generally recommend a baseline test to assess for underlying imbalances or deficiencies that may be related to testosterone deficiency or mimic its symptoms. This includes:

• Metabolic panel - cholesterol, liver and kidney markers, CRP (an inflammatory marker), blood sugar

• Thyroid panel - TSH, fT3, fT4, anti-TPO

• Nutrient panel - vitamin B12, vitamin D 25-hydroxy, zinc, calcium, ferritin (= iron stores)

• Hormone panel - cortisol, DHEA-S, estradiol, progesterone (in women), FSH, LH, SHBG; “all hormones interact”

Testosterone Panel  

• Total testosterone - A measure of all testosterone in the blood, including both free and bound forms.

• Bioavailable testosterone - A mixture of all non-SHBG-bound testosterone, including both free and albumin-bound testosterone. SHBG-bound testosterone is not readily used (SHBG binds testosterone ‘tightly’) while albumin-bound (binds testosterone ‘loosely’) and free testosterone can be more easily used by your body. See below for more notes on albumin and SHBG.

• Free testosterone - A measure of the testosterone not attached to proteins. I personally deem this the most important of the three because it measures the form of testosterone most easily used by your body. ‘Normal’ lab ranges are 115-577 pmol/L, an average value derived by testing a subset of males that are of all ages, sizes, and health levels. Hence, one may deem the mid to high range more typical for a middle-aged, healthy male.

Testosterone labs should be tested in the morning (before 10) to avoid registering the normal circadian dip that occurs in the afternoon.

Why SHBG is Important
Sex Hormone Binding Globulin (SHBG) is a protein made by the liver. It roams around in the blood and when it comes into contact with testosterone it binds it tightly (“kidnaps it”). This makes testosterone unusable by the rest of the body (e.g., muscles). Thus, one might have high total testosterone but still be experiencing symptoms of low testosterone (or have low free testosterone) because SHBG is high and holding testosterone captive. On the other hand, one might have low to normal total testosterone, yet present with symptoms of high testosterone (increased muscle size, acne, male pattern baldness, PCOS) because SHBG is low and more testosterone is roaming freely in the blood readily available for use. Reasons for high SHBG include liver disease, HIV, hyperthyroidism, anti-seizure medications, advancing age, lifestyle (smoking, alcohol, stress, weight training without proper nutrition, excess sugar). 

Albumin, another protein that roams around in the blood, can also bind testosterone but not as tightly (“a less committed kidnapper”). Thus, albumin-bound testosterone can still be used by the body and is considered bioavailable. Free testosterone, however, is not bound to anything and is the most “available” for the rest of the body to use.

Why LH and FSH are Important?

• Low T with low LH/FSH – This pattern is indicative of sleep and nutrient deprivation and/or elevated stress (interfering with signals from the brain to the testes). In this scenario, testosterone levels should first be treated with lifestyle optimization.

• Low T with high LH/FSH – This suggests the problem is sourced at the testes (i.e. primary hypogonadism) and, in younger persons, one should rule out Turner syndrome (women) and Klinefelter syndrome (men). Testosterone replacement therapy may be a good treatment option in this case.

• High T with suppressed LH/FSH - A result of exogenous testosterone replacement.

Monitoring Labs on Testosterone Replacement Therapy (TRT)
If on TRT, labs should be measured at 3, 6, and 12 months, and every year thereafter. This will help ensure adequate dosing as well as monitor for associated risks and/or adverse effects. The laboratory panel should include testosterone (free and total), calcium, liver function, CBC + differential (hematocrit, hemoglobin), cholesterol, PSA, and estradiol. A digital rectal examination of the prostate should be done at 3 to 6 months and 1 year after therapy, then annually thereafter. A PSA increase greater than 1 ng/mL within the first 6 months may reflect the presence of pre-existing cancer and warrants cessation of therapy. If hematocrit level rises greater than 54%, testosterone should be discontinued until it normalizes. If it is restarted after normalization, it should be re-introduced at a lower dose with careful monitoring.

Salivary or Serum - Which is Better?
Testosterone can be tested via the saliva or blood (serum). The choice is mostly practitioner preference as they both come with pros and cons. Serum testosterone has well-established reference ranges and is the conventional method of choice. However, the ‘normal’ ranges are fairly large, the sample only represents a snapshot in time, and it must be performed at the lab, ideally first thing in the morning. Salivary testosterone is easy, convenient and non-invasive as the samples are taken at home by spitting into a tube at certain time intervals throughout the day. It is more accurate for assessment of transdermal hormones. Unfortunately, it’s not as accurate for sublingual forms nor is it accepted by all insurance carriers.

Natural Ways to Boost Testosterone
The most important factor to consider when treating low testosterone is “why is it low in the first place”? Is it a pathological deficit or is it something within our lifestyle that is diminishing our levels? Here are a few lifestyle recommendations that can naturally support testosterone:

• Nutrients – To best support testosterone production I would suggest a high protein diet (consuming at least 1 g/lb of bodyweight/day), adequate caloric intake of high-nutrient foods, 2:1 simple carbs:protein post-workout, high cholesterol foods such as whole eggs and hormone-free grass-fed beef (sex hormones are made from cholesterol) and foods rich in zinc (high in oysters and pumpkin seeds), vitamin D (catch rays, eat fish), magnesium (high in leafy greens, avocados, nuts and seeds), and boron (avocado).

• Lifestyle – Healthy amounts of exercise (not too much or too little), prioritizing sleep, sex, and stress-management can all positively impact testosterone levels.

• Herbs - Overall, there is limited evidence to suggest that herbs actually move the testosterone needle. However, they can impact libido and other symptoms of testosterone deficiency. For example, tribulus (Tribulus terrestris) does not raise testosterone but may improve libido, erectile dysfunction, intercourse, and satisfaction of orgasms. Damiana (Turnera diffusa) can support libido and mood. Tongkat ali (Eurycoma longifolia) is shown to lower cortisol and improve free testosterone, erectile dysfunction, libido, and semen volume. Yohimbe (Corynanthe johimbe) improves erectile and ejaculatory dysfunction but may cause adverse effects including tachycardia, hypertension, and anxiety. Shatavari (Asparagus racemosus) is known as the ‘Queen of Herbs’. It is an aphrodisiac as well as a rejuvenating and female reproductive tonic used for fertility, hormonal imbalance (e.g., PMS, menopausal disturbance), and sexual debility, said to “give her capacity to have 100 husbands”. Other herbs that may be supportive include horny goat weed (Epimedium), maca (Lepidium meyenii), Siberian ginseng (Eleutherococcus senticosus), ashwagandha (Withania somnifera), and velvet bean (Mucuna purens). Whether exploring natural or pharmaceutical interventions to enhance testosterone, proceeding with caution is important so as not to disruptdd the endocrine axis (i.e., “natural” doesn’t mean no side effect of shutting down endogenous production).

• Exercise – To best support testosterone and muscle growth I suggest incorporating compound lifts (e.g., snatch, clean, deadlift, squat) with lots of volume (30 - 50 reps total) and intensity.

Testosterone Replacement Therapy (TRT)
Are you taking the above lifestyle considerations seriously and still not getting the results you want? Talk to your medical doctor or nurse practitioner about TRT.

Note: Naturopathic doctors in Canada cannot prescribe testosterone. 

Top Candidates

• Andropause (hypogonadism affects ~40% of men aged 45 or older)

• Delayed ejaculation

• Female to male transexuals

• Post-menopausal women (if symptomatic)

• Post-operative recovery and treatment of debilitating disease (for anabolic effects)

• Primary hypogonadism (although intramuscular HCG is the drug of choice) and hypopituitarism

• Severe adrenal fatigue, assuming other avenues have been exhausted and estrogen is within normal range

• Surgical menopause, especially if ovaries removed (climacteric ovary contributes to 50% testosterone and 30% of androstenedione to circulation)

• Testosterone deficiency (free T at the lowest quartile of normal range for reproductive ages (20-40), especially with metabolic dysfunction

Contraindications

• Benign prostatic hyperplasia (BPH)

• Breast cancer

• Medications such as warfarin (due to potential interactions)

• Polycythemia vera

• Pregnancy or breast-feeding (due to teratogenic potential)

• Prostate cancer and those at high-risk (i.e., first degree relatives, of PSA>3ng/mL)

• Severe cardiac, liver or kidney disease

• Sleep apnea, untreated

Potential Risks

• Testicular shrinkage and decreased fertility - Testosterone replacement therapy stops the body's own natural production of testosterone and sperm. Testicular atrophy and infertility are likely to occur if uninterrupted testosterone replacement is administered typically for greater than two years. Hence, one might consider taking testosterone for 6 months then take a 1-month break (HCG is sometimes used during this period to help prevent sterility). Many who are on consistent testosterone therapy stay on it for life.

• Cardiovascular risk - Testosterone thickens the blood, thereby increasing the risk for stroke or myocardial infarction (MI). This is why it’s essential to monitor hemoglobin (Hgb) and hematocrit (Hct) levels to ensure there are no signs of polycythemia. Some studies also suggest it increases LDL (“bad cholesterol” and decreases HDL (“good cholesterol”), possibly leading to coronary artery disease. Risk is heightened for those who already have metabolic concerns (e.g., high cholesterol and/or blood pressure, diabetes). All this being said, cardiovascular risk is controversial. A counterargument is that testosterone has cardioprotective effects (lowers fat mass, blood sugar, lipids) and low testosterone can increase the risk of cardiovascular disease.

• Prostate growth – Research has shown prostate size to increase by 12% after an 8-month duration of testosterone at 160 mg/day. Thus, one must be wary about TRT in conditions with prostate growth (i.e., benign prostatic hyperplasia (BPH) and prostate cancer.). Administration is controversial in BPH as it increases prostate volume but reduces urinary symptoms. Finasteride 5 mg daily is sometimes given in combination with testosterone as it may slightly counteract the increase in prostate size (note that Finasteride 1 mg daily is more typical for male pattern hair loss). It is, however, absolutely contraindicated in prostate cancer and those at high-risk as it has been shown to increase progression. Prostate-specific antigen (PSA) and digital rectal exams are two important monitoring tools to ensure testosterone is not accelerating undetected prostate growth in an otherwise healthy male on testosterone replacement therapy.

• Symptoms of high androgens (e.g., acne, male pattern hair loss, excessive body hair, deepening voice, aggression, irritability) - If testosterone is being dosed in excess (or if one has a genetic predisposition to an overactive 5-alpha-reductase enzyme, which converts testosterone to DHT, an androgen that has similar effects to testosterone but is 5x more potent) symptoms of high testosterone may be experience. In this case, talk to your doctor about decreasing your dose.

• Symptoms of high estrogen (e.g., swelling, weight gain, PMS, gynecomastia in males, breast pain, visceral obesity) - This can occur as a result of ‘estrogen aromatization’ (when a complex of enzymes converts testosterone into estrogen). Gynecomastia and breast pain have been seen in 10 to 25% of men on TRT. High stress and testosterone can increase conversion to estradiol. Monitoring estradiol can determine if this is a problem.

• Breast cancer (in men and women) - If aromatization of testosterone to estrogen occurs the risk of breast cancer could be increased (high estrogens “feed” breast cancer). In one study postmenopausal women receiving E + T had a 2.5-fold increased risk of developing breast cancer versus E-alone or no HRT. Conversely, research suggests topical forms are free of breast cancer risk. It’s also interesting to note that although testosterone can increase the risk of breast cancer, it can also be used as a treatment for some types of breast cancer (confusing, I know). This is because high-dose androgens (e.g., testosterone) invoke negative feedback on the pituitary to reduce estrogen production and inhibit estrogen-stimulated breast cell proliferation.

• Menstrual irregularities – Testosterone can cause ovulation from occurring and result in complete cessation of the menstrual cycle.

• Obstructive sleep apnea (OSA) – Some studies demonstrate that OSA occurs in men undergoing testosterone therapy and resolves when treatment is stopped. The mechanism is poorly understood.

• Liver disease – Once again, studies remain controversial. However, some studies do suggest potential for impaired liver function (specifically with oral testosterone) so labs should be carefully monitored.

• Fluid retention and edema - Testosterone therapy is known to cause water retention and should thus be used with caution in individuals with chronic renal insufficiency and/or cardiac heart failure.

Administration

• Men – Testosterone dose and form of administration can differ depending on the individual. Topical testosterone (e.g., gel) may be prescribed due to ease of use, however, bioavailability may be compromised. Intramuscular (IM) injections are usually advised against as they are quite invasive and can result in peaks and valleys rather than consistent levels. Subcutaneous injections are another option, typically administered twice per week, providing good bioavailability and reduced peaks and valleys. HCG is sometimes recommended to preserve fertility or to give an additional “kick-start”.

• Women – Much lower levels are required for women relative to men due to lower baseline levels. Healthy women naturally produce about 3 mg/day and transdermal testosterone is usually given at doses 0.25-2 mg daily.

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