The loss of muscle mass, sexual dysfunction, depression, mood issues, low libido, loss of bone density, fatigue, increased body fat - these are just some of the symptoms of low testosterone. And it is something that is becoming more and more common, as testosterone levels plummet in males in recent decades. 

If you notice that you are having symptoms like decreased libido, erectile dysfunction, depressed mood, low motivation and drive to do things that used to be fun, difficulties maintaining and building muscle, and difficulties with concentration and memory, it might be highly advisable to get your testosterone levels checked.

Benefits of Maintaining Healthy Testosterone Levels

• Better mood and fights depression
• Decrease in body fat
• Builds and maintains muscle mass
• Improved cardiovascular health
• Helps maintain optimal bone density
• Increases libido and sexual function
• Improves metabolism
• Heightened sense of well-being
• Better sleep quality
• Increased energy levels
• Improved mortality rate

A simple blood test should measure your total testosterone, free testosterone, LH, FSH, estradiol and SHBG levels.

If these levels are bordering on the low side and you do not want to take hormone replacement therapy, which typically involves injections or topical gels, there are some ways that you can boost testosterone levels naturally, aside from proper diet, exercise and adequate rest and optimizing your responses to stress.

Declining Testosterone Levels: Are They Really Lower Than Our Ancestors?

In men, testosterone levels typically hit a peak somewhere around 25 to 30 years of age. From there things start to go downhill, thereafter dropping approximately 1-2% each year.

By retirement age, the party is over, as testosterone levels are found to be only 40-50% of what they once were in your, and levels and may be lower yet due to stress and other similar lifestyle related issues such as diet, exercise, and sleep patterns.

We all should be concerned with maintaining optimal testosterone levels to have increased lean muscle mass, less body fat, improved mental and physical energy, and improved general well-being, healthier collagen levels (thus less wrinkles), better memory, improved bone mass and more.

In adult males, almost all testosterone is produced in the testes between 3 mg and 10 mg each day. The adrenal glands produce the remaining amount of this hormone.

The hypothalamus and pituitary glands produce lutenizing hormone (LH) and follicle-stimulating hormone (FSH), which in turn direct the Leydig Cell in the testes to ramp up testosterone production. This whole process is referred to as the hypothalamic–pituitary–gonadal axis (HPG axis).

About a decade ago, the Canadian network, The CBC, showed a documentary called " The Disappearing Male". It is a pretty alarming documentary, delving into how endocrine disrupting chemicals, ubiquitous in our world, are destroying testosterone and fertility levels among boys and men alike.

Proven Ways to Increase Testosterone Naturally: Adaptogens and Herbs

Tongkat Ali

One of my favorite herbs that I have used successfully to increase my free testosterone is Eurycoma longifolia - a medicinal herb commonly called tongkat ali or "longjack" found in South East Asia (Malaysia, Vietnam, Java, Sumatra, Thailand etc).

The way that tongkat ali works to increase testosterone naturally is by reducing SHBG (sex hormone binding globulin) to increase free, or "unbound" testosterone, resulting in elevated free testosterone, improved sex drive, less fatigue, and improved sense of overall well-being.

Other benefits include reduced lethargy and depression, and it also appears to have significantly aid in restoring a damaged HPA axis and thus improving hormone balance (cortisol/testosterone ratio).

Tongkat Ali also aids in improving psychological mood in people exposed to typical modern day stressors, such as aging, dieting, and exercise stress.

The caveat is to get the real thing and to get it at 200:1 strength. The real tongkat ali comes from Indonesia or Malaysia and is a dark brown color and smells and tastes nasty due to the quassinoids.

Epimedium

Sometimes called "Horny Goat Weed", epimedium is one of many herbs mainly used in Traditional Chinese Medicine used to treat erectile dysfunction in men, as its primary ingredient icariin, works as a natural phosphodiesterase V PDE5 inhibitor (which is exactly how Cialis, Viagra, Levitra etc work).

It is believed at this point that it increases testosterone by stimulating the activity of cGMP, a secondary messenger in the testes.

Epimedium stimulates the Leydig cells (in the testes) which are responsible for the stimulation and production of endogenous testosterone. (more below on the why you want to increase cAMP)

Anecdotally, I took it for a mere 8 weeks and it raised my total testosterone by 160%. It also raised my DHEA from just above low normal to the high end of normal, and I suspect that this is the mechanism by which it raises testosterone, although I have been unable to find research to support this.

Another thing I noticed from a 24 hour saliva cortisol/DHEAs test I did after taking 500mg of Epimedium daily is that my am cortisol was a lot lower and my am total testosterone elevated, which also makes sense as cortisol and testosterone have a sort of inverse relationship - one goes up, and the other tends to go down, likely due to the fact that both stress and sex hormones are made from the master hormone - pregnenolone - and when one process uses more of it, it "steals" it from the other processes.

But its benefits do not stop there. Epimedium also boosts testosterone production and also tweaks neurotransmitters, particularly dopamine and improves cognition with nootropic properties.

Forskolin/Coleus Forskohlii

The supplement Forskolin is derived from the adaptogenic herb, Coleus Forskohlii. It is used in naturopathy to improve thyroid function as well as boosting testosterone. (it is also very common that when one's thyroid function improves, so do their testosterone levels).

Forskolin also is believed to have lipotropic or fat burning properties, which also helps our purposes.

Forskolin increases testosterone naturally by increasing cyclic AMP (or cAMP) levels in the testes, just like epimedium does, but without any direct action on lutenizing hormone ("LH").

There is one of many studies done over a decade ago that used 250 mg Forskolin twice a day for a 12-week period and it was demonstrated to favorably alter body composition while at the same time, increasing bone mass and serum free testosterone levels in overweight and obese men. This sounds really promising.

Again, because Forskolin also improves thyroid function, it is possible that the improved body composition and fat loss is due to this.

Some other studies suggest a 15-20% increase in testosterone. (Many bodybuilders in contest preparation will also take synthetic thyroid hormones, T3 and T4, to increase metabolic activity and induce a fat-burning state)

T-Nation wrote a great article about this some time ago and have it in one of their products.

They cite research that some of the benefits of increasing cAMP are: lowered blood pressure, inhibition of platelet stickiness/clotting, increased blood flow and better cardiopulmonary function.

Fenugreek

Fenugreek is another herb with effects on hormones. It originates in India and is one of the main ingredients in most curry powders and Indian cooking. It is also the main ingredient in the supplement Testofen which is 50% fenugreek extract.

It has several beneficial health effects, mainly increasing free testosterone, boosting libido and lowering blood sugar.

Fenugreeks increases testosterone by inhibiting the 5-alpha reductase enzyme responsible for the conversion of testosterone to dihydrotestosterone (DHT), which is another more powerful androgen.

In one study, men receiving 500 mg of fenugreek daily experienced a pretty significant increase in their total testosterone (6.57%) and bioavailable testosterone (12.26%).

In any event, inhibiting prostatic conversion of testosterone to DHT, prostate size can be reduced. The dosage for men would be 500 to 600mg of a standardized fenugreek formula.

Shilajit

Another gem to use is Shilajit, also called the "Indian viagra". This herb is another of the so-called "adaptogens" which works by increasing testosterone levels. Shilajit is the primary bioactive form of Fulvic Acid, which alone has many useful health benefits. 

In one study done back in 2010 on 60 infertile male patients, the subjects increased their testosterone levels by 23%, as well as improving their sperm count and sperm motility.

One thing to note though is that the dosage used, 200mg Shilajit (54.8% Fulvic Acid), is a lot more than what most Shilajit containing supplements have.

Another study which also greatly boosted the subject's total testosterone levels used 250 mg twice a day for 90 days. According to Examine.com:

200mg Shilajit daily for 90 days in infertile men is associated with an increase in Follicle-Stimulating Hormone (FSH) by 9.8%, with no significant influence on Luteinizing Hormone (LH) in serum.

Cordyceps

Cordyceps is a type of mushroom - a species of fungus which has been used in Traditional Chinese Medicine for centuries for maladies such as asthma, kidney problems and as an anti-aging tonic. it is a proven anti-oxidant, anti-tumor supplement with powerful anti-inflammatory and immune boosting properties.

This beneficial fungus can also improve oxygen utilization, helping with aerobic performance.

Cordyceps improves recovery time and increases energy by elevating ATP Levels. Adenosine triphosphate is what provides energy to the muscle cells, which is why this supplement is great for athletes as well as the elderly.

Cordyceps, according to one 2011 study, also stimulates the Leydig cells in the testes to produce more testosterone by inducing StAR (steroid acute regulatory protein) protein expression locally.

Stinging Nettle Root

Nettle is a medicinal plant traditionally used kidney disorders, arthritis and gastrointestinal tract issues. Its astringent properties make it a go-to supplement for urinary tract and bladder infections and also in treating Benign Prostatic Hyperplasia (BPH) as it reduces the enzyme 5 alpha reductase, diminishing the conversion of testosterone to DHT.

Similar to Tongkat Ali, the lignans (polysaccharides) in nettle bind to sex hormone binding globulin (SHBG), leading to increases in free testosterone.

Typically, doses of ranging from 500-600 mg are used. There are also very good teas out there with pharmakopia grade herbs, such as the one sold by Traditional Medicinals teas, which contains 2000 mg stinging nettle leaf.

In 2008, there was some interesting research suggestive of nettle also being a mild aromatase inhibitor, which diminishes the conversion of testosterone to estrogen via a particular lignan in the leaf, 9-oxo-10,12-octadecadienoic acid.

Prohormones, Vitamins and Minerals

DHEA

DHEA or Dehydroepiandrosterone, is an endogenous steroid prohormone in the sex hormone cascade acting as a precursor to our androgen production, such as testosterone.

It is produced in the adrenal glands (tiny glands the size of a walnut that sit atop of your kidneys which make various hormones and neurotransmitters). DHEA is converted by the body into testosterone and various other sex hormones.

As with testosterone, our production of DHEA peaks during our late 20’s or early 30’s. As we age, DHEA production begins to decline.

As with increased testosterone, the benefits of DHEA include: better immune function, improved mood, better short term memory and cognition, better libido and sexual function, increased bone density, more muscle mass.

One of the things that I see is that the dosages recommended are far too high. It is common to see 100 mg a day prescribed, when we naturally only make around 10 and 15 mg a day.

I think 5 to 10 mg a day is a sufficient dose, as it is possible that DHEA will also increase estrogen levels as well and is best taken judiciously with an estrogen blocker. I would not take more than 10 mg a day on a long term basis.

Zinc

If you're not already supplementing with zinc, you might want to look at the research which correlates low testosterone levels with zinc deficiency. Zinc, an important mineral in our diets, is vital for testosterone production.

Having enough zinc in our diet, or through supplementation, will help optimize the body's production of not only testosterone, but also growth hormone and insulin-like growth factor-1 (IGF-1) - two very important factors in muscle growth as well.

According to a survey by National Institutes of Health, an estimated 20-25 percent of older adults have inadequate zinc intakes.

A daily intake of zinc is required to maintain a steady state because the body has no specialized zinc storage system.

Since zinc plays such an important role in modulating serum testosterone levels in men, supplementation is advisable, but at a dosage of less than 40 mg a day, as that is the recommended adult upper limit, and exceeding that can interfere with copper, which can cause other issues.

Magnesium

Another supplement that is part of my daily stack is magnesium. It is the mineral that is most quickly depleted when under stress and is vital to recovery from hard training sessions as well. But it also is critical to boosting levels of both free and total testosterone.

According to research, supplementation with magnesium at 10 mg magnesium per kilogram body weight (something like 750 mg), increased both free and total testosterone values in sedentary and in athlete control groups alike.

The increases in the research were also higher in those who exercised than they were in sedentary individuals. Something very encouraging for us!

As with the case of the research with zinc, magnesium also optimizes both testosterone and IGF-1 levels, as well as playing a huge role in producing enzymes that help with vitamin D absorption, blood glucose regulation, and on top of facilitating a direct increase in testosterone, it is vital to optimal protein synthesis.

Anecdotally, I have been taking 300 mg of magnesium bisglycinate at night about an hour before bedtime and 150 mg in the morning and it has helped immensely with my sleep quality - and good long refreshing sleep is also associated with higher testosterone levels.

Vitamin D

Perhaps the most-studied supplement of them all, Vitamin D, has lots of proven research linking it to testosterone levels.

Men with low levels of vitamin D not only have a lot of the symptoms of low testosterone such as lowered bone density, but also higher levels of estrogen as well along with less lean body mass and elevated levels of depression, impaired fertility and cardiovascular disease.

In various studies, subjects who received vitamin D had statistically significant increases in testosterone compared to those who had taken placebo.

Typically, total testosterone levels rose by 3 nmol/litre to 13.4 nmol/litre after 12 months.

A similar trend occurred with unbound bioavailable testosterone and free testosterone. The vitamin D receptor (VDR) is involved in activating hundreds of genetic switches involving muscle growth and androgens. Supplementation with vitamin D will increase the activity of the androgen receptor and VDR.

Vitamin D is also thought to play a role in limiting testosterone from being converted to estrogen via the aromatase enzyme and also lowers SHBG, enabling higher free testosterone.

One caveat with vitamin D supplemention is to take it in the morning, as it also has an effect on the pineal gland to shut down melatonin production.

Since melatonin production, necessary for good sleep, is usually ramped up at night by the pineal gland in a normal circadian rhythm, and vitamin D has the same effect on the pineal as sunlight, shutting down melatonin, it is best to take vitamin D in the am (as we evolved to see sunlight in the am).

Vitamin A

Another vital supplement for normalizing test production is Vitamin A, which has the ability to the blood-testis barrier, as its principal biologically active derivative, retinol, which increases basal testosterone production.

One of the factors responsible for us not getting as much vitamin A as our ancestors is the lack of organ meats in our diet, which happen to be the highest sources of vitamin A.

In the 1950s and 60s, taking dessicated liver was popular among bodybuilders with people like the late Vince Gironda recommending it. Our ancestors ate organ meats on a weekly basis.

From the Weston A. Price Foundation:

One experiment using guinea pigs, which corroborates the many experiments done with rats, found a decrease in plasma testosterone associated with a deficiency in vitamin A.2 A human study comparing the dietary intakes of 155 pairs of male twins found a correlation between testosterone levels and vitamin A intake.3

Vitamin K

Like Vitamin D, Vitamin K is also one of the fat-soluble vitamins with two forms: phylloquinone, the plant-based vitamin K1 found in green vegetables, and menaquinone, the animal-based "K2" form.

One of the biggest benefits of vitamin K is to work in synergy with vitamin D to get calcium to your bones.

Without K as a transport, the excess calcium float around your bloodstream, leading to arterial plague. As it happens, K is also vital for proper blood coagulation.

Aside from these benefits, vitamin K was found in research on rat models at a human equivalent 12mg/kg for a 5 week period. The results? They found that vitamin K2 boosted testosterone by an average of 56%.

Boron

Last but not least, I thought it would be good to include this obscure trace mineral that has some research behind it in terms of its ability to increase free testosterone levels and decrease estradiol.

Boron increases serum levels of magnesium, vitamin D while decreasing estradiol and sex hormone binding globulin (SHBG). Low levels of boron are also associated with reduced testis weight and sperm count.

In one human study, participants were given 10mg boron for a 7 day period. The subjects all had a significant increase in testosterone levels, along with significant decrease on sex hormone binding globulin (SHBG). Mean plasma free testosterone increased and the mean plasma estradiol decreased significantly.

Some Cautions

As when starting any supplement, the best policy is to "start low and go slow". I would take a lower than recommended dose to see how you react to a new substance. These medicinal and adaptogenic herbs are not innocuous and can affect different people in different ways.

For example, adaptogens like Rhodiola can spike dopamine, and because of this, its use in people with bipolar or schizophrenia is cautioned.

Some of these herbs not only have an effect on neurotransmitters such as serotonin, dopamine and adrenaline, but also on hormones as I've mentioned. This is not surprising as the intricacies of our neuroendocrine system is mind-bogglingly complex.

Another thing I would do is to try any new supplement in isolation and stay away from those supplements with have a laundry list of ingredients. If one thing is working for you and something else is causing a negative side effect, it is impossible to know which is causing what.

For example, year-round I take some basic supplements: a good vitamin B complex, 1000 mg vitamin C, 4000-5000 iu vitamin D, 30 mg zinc bisglycinate and about 600 mg magnesium bisglycinate.

To that base stack I test things in isolation, like Tongkat Ali for example. This approach has helped me immensely in determining how I react to things.

Also, it is important to note that the main building block of testosterone (and all hormones) is cholesterol. If you are deficient in it, you are not doing yourself any favors.

So eggs, olive oil, coconut oil and grass-fed butter are your friends. (The wonderful Weston A. Price has lots of information on this).

For those on a vegan diet, I would ensure that you are getting a lot of coconut and olive oil and good fats from nuts.

In Closing

One last thing I would also suggest is to also have your thyroid and adrenal function checked. I recently read something by renowned neuroendocrinologist Dr. Romeo B. Mariano, where he wrote that the best approach to fixing any hormonal deficiency is to first fix any issues with adrenal function, and then fix a potentially low thyroid, and then and only then when those systems are working efficiently proceed to address testosterone function.

He has written a lot on the subject of testosterone replacement and hormones  and is worth a read on this topic. A sample of this is:

To summarize some issues a lot (since the actual mechanisms can be mind-bogglingly complex):

Chronic or traumatic stress may lead to hypothalamic-pituitary-adrenal axis dysregulation (the term which I believe is more accurate to use than the term "adrenal fatigue"), HPA dysregulation for short.

HPA dysregulation leads to lower production of adrenal cortex signals/hormones. This includes lower cortisol and/or DHEA, progesterone, pregnenolone, testosterone, estradiol, or aldosterone.

The primary signal for stress is norepinephrine. Norepinephrine is in a positive feedback loop with corticotropin releasing hormone. This positive feedback loop is interrupted by cortisol signaling. To increase norepinephrine, the brain has to also reduce production of some or all of the control signals that suppress norepinephrine signaling. These include reductions in serotonin, dopamine, GABA, etc.

Stress (particularly if it is a perceived threat), may lead to an increase in pro-inflammatory cytokine signaling from the brain and from the immune system (which is directly innervated by neurons of the sympathetic nervous system - the primary norepinephrine-releasing neurons of the nervous system). Stress may also lead to an increase in histamine signaling from brain mast cells. These changes lead to an activation of the immune system. These changes in large excesses may lead to an increase in inflammatory processes. The loss of anti-inflammatory signaling - which includes cortisol, DHEA, progesterone and testosterone - exacerbates these pro-inflammatory changes.

Excessive pro-inflammatory cytokine signaling may trigger automatic defensive programs in the brain. Defensive programs may induce behavioral changes including depressed mood, loss of interest or motivation in activities, loss of enjoyment from activities, social isolation, changes in sleep including the desire to sleep excessively.

There may be a loss of energy from excessive pro-inflammatory cytokine signaling. The actual mechanisms of the loss of energy are not clear. I currently speculate that perhaps there may be impaired brain astrocyte conversion of thyroxine (T4) to triiodothyronine (T3) - which leads to a hypothyroid central nervous system with a euthyroid body (as in Alzheimer's disease). Perhaps the increase in pro-inflammatory cytokines is one of the signaling problems leading to HPA dysregulation, aside from excessive norepinephrine signaling. However, other regulatory systems may also be involved - such as the opiate signaling systems (which also involve dopamine signaling).

HPA dysregulation, from whatever cause, leads to a loss of energy. The loss of energy production, however, under some circumstances. These circumstances include bipolar disorder and attention deficit/hyperactivity disorder with hyperactivity. In these cases, norepinephrine production is an effective signal for energy.

Nutrition plays a large role in the development of HPA dysregulation. Omega 3 vs. Omega 6 balance helps determine the balance between inflammation and anti-inflammation. Various nutrients (such as the B-vitamins, fat soluble vitamins, magnesium, etc) are cofactors for many of the processes involving signal production. Vitamin A and D are generally anti-inflammatory signals. Vitamin D reduces insulin resistance (which helps the body tolerate low blood sugar from impaired cortisol signaling), increases serotonin and dopamine production. Vitamin A helps regulate the sensitivity to various hormones/signals such as thyroid hormone.

The other endocrine signaling systems such as the reproductive system are in play. Testosterone helps reduce norepinephrine, increases dopamine production. It also suppresses adrenocorticotropin releasing hormone and directly inhibits adrenal cortex activity - this may be significant depending on the sum of signaling interactions and problems a person has. Estrogen acts similarly to a monoamine oxidase inhibitor - thus increasing serotonin, norepinephrine and dopamine (but serotonin primarily). Estrogen in relative excess may be pro-inflammatory, reduces free thyroid hormone. Thyroid hormone signaling loss is compensated by an increase in norepinephrine production with simultaneous activation of adrenal cortex signals. Over time, however, this compensation may fail as HPA dysregulation occurs. Insulin, glucagon, the incretins, etc. also have a role. Insulin, itself, is pro-inflammatory. Growth hormone has a calming effect and is anti-inflammatory. Etc. etc. etc. etc.

The entry point of all these processes is stress. This is represented primarily by norepinephrine signaling. However histamine (from brain mast cells) and pro-inflammatory cytokines (from brain microglia) are also involved in the process. Stress induces responses that are ostensibly designed to improve survival. The problem is that in the modern world, these responses may be dysfunctional instead.

Given the complexity of the interactions involved, a single intervention may or may not work. Which direction an intervention goes depends on the sum of the changes that occur as a result of that intervention. In psychiatry, the usual answer to a question is "It depends."

Stress is the entry point. Environmental and behavioral interventions would clearly help with few downsides.

Low dose testosterone may help, particularly in women, by helping to reduce norepinephrine and increasing dopamine signaling, and helping to reduce pro-inflammatory signaling. Low dose testosterone would not help in men since it may do nothing or it would suppress endogenous production of testosterone, leading to lower overall testosterone levels. Men would need replacement doses of testosterone. Testosterone, however, may also worsen adrenal cortex function depending on a person's susceptibility to this. In men, exogenous testosterone treatment also suppresses testicular thyroid releasing hormone production, leading to a loss of thyroid hormone production, which then leads to an increase in norepinephrine production. This is why in certain men, even if hypogonadal, testosterone treatment is intolerable. The rest of the system has to be optimized before testosterone treatment can be done.

Tamoxifen (I would prefer this to Clomiphene due to the visual changes that can occur with Clomiphene) is a weak estrogen. This blocks the stronger estrogens from being sensed by the brain. This then causes the brain to release more Luteinizing Hormone to stimulate testosterone production, leading to estrogen production. The increase in testosterone would have the effects listed previously. The problem is that Tamoxifen also blocks estrogen. This leads to lower estrogen signaling activity. Estrogen helps control norepinephrine by increasing serotonin and dopamine production. Estrogen is also needed to improve sensitivity to testosterone by increasing testosterone receptor production. Estrogen is also important in generating energy, motivation, drive, competitiveness, sex drive (libido). Estrogen (particularly in women) is important for neuron growth and memory. The loss of estrogen signaling, depending on the balance with testosterone, may lead to negative effects. If testosterone production is driven high enough, then perhaps this would improve things overall. This is particularly true in men. However, in women, this may not occur and destabilization of the system and dysfunction may occur instead. This is why many women do not like treatment with Tamoxifen or Arimidex for breast cancer.

Cortisol treatment alone may or may not work. Cortisol treatment in sub-replacement doses helps because it helps break the norepinephrine-CRH positive feedback loop. Cortisol also acts in the brain to improve concentration/focus by allowing the brain to ignore emotionally distracting memories or information. Cortisol also is the most important anti-inflammatory signal that reduces immune system activity. Cortisol triggers gluconeogenesis - helping improve blood sugar production. etc. etc. Thus it can be a useful component of treatment. However, Cortisol treatment alone also suppresses adrenal cortex activity. Thus, there is also a loss of pregnenolone, progesterone, DHEA, testosterone, estradiol, aldosterone, etc. If this loss is large enough, then the person may be worse off than without treatment. Since the majority of these other signals are calming, help control norepinephrine, are anti-inflammatory signals, a significant loss may cause the opposite intended effect of cortisol treatment. This is where some people become more tired, get "brain fog", become more anxious, etc. on cortisol monotherapy.

A systematic treatment has to be considered to address the multiple issues that invariably occur, contributing to HPA dysregulation. Single modality treatments may help - particularly in those people who don't have large problems in the rest of their system. But often, in more severe cases, they don't. A systemic approach would then be needed. I would count the person who responds to monotherapy as very fortunate.

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