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All You Need to Know About Testosterone Boosters

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You’ve decided that you want a more muscular physique, a stronger max in the gym and a body composition that shows you mean business.

To get there you know that you need to train hard and eat well and do everything you can to optimize your testosterone levels. Hopefully by now you’ve heard that testosterone boosters are the way to go. But the problem is that you can’t find enough information about whether they work or which ingredients to choose.

In this article we’ll give you all of the answers you’re looking for. It’s a detailed tour of why this type of supplement can help you achieve your goals and which are the best ingredients to choose.

If your’re after a comprehensive guide to testosterone boosters then this is the place to be.

What is Testosterone?

Testosterone is the most anabolic of your male hormones. It is responsible for maintaining muscle mass and strength as well as improving body composition and athleticism. It also enhances sexual appetite, performance and libido and optimizes health too.

Produced by the Leydig cells of the testes in men, and a small amount in the ovaries in women, the main aim of this hormone is to control the development of male characteristics. It is classed as an androgen as it is a naturally occurring steroid hormone. It has two main categories of effect:

  • Anabolic – actions primarily include development of male characteristics – increased strength, voice deepening and hair growth.
  • Androgenic – actions include increased protein metabolism and inhibition of protein breakdown.

From the onset of puberty your T levels increase dramatically. When this happens you notice a big change in your growth, voice, muscle and hair development and height. It really shows the power and potency of this hormone.

How Do Clinicians Measure Testosterone Levels?

Testosterone can be measured either by blood tests or by a simple saliva test.

Normal levels should be between 300-1000 ng.dL. Anything lower than that and it’s too low to optimize health or performance.

A large proportion of blood testosterone circulates bound to two main proteins, albumin and sex hormone binding globulin (SHBG). This means that only a small amount (around 3% or so) is bioavailable, or ‘free’ to be taken up by your tissues and cells.

Some of your free T is converted to a very potent androgen called dihydrotestosterone (DHT). However, some of it is converted into estrogens via aromatase enzymes. If estrogen gets too high then you start to develop belly fat or ‘man boobs’ so it is important to limit aromatization wherever possible.

Good healthy T levels have to balance out all of these enzymatic reaction and other hormones. Get this right and you’ll reap the rewards.

The Consequences of Low T

Testosterone levels should remain high throughout your twenties. Once in your thirties though it starts to decrease by about 1% per year.

If levels drop below 300 ng.dL you have ‘low T’. The clinical term for this is hypogonadism.

When this occurs you may lose muscle mass and strength and your overall athleticism will suffer. You will lose your libido and your sexual performance will decrease rapidly. Lastly, you will begin to develop belly fat which in turn lead to heart and metabolic illness or early death.

During this time that you need to do all you can to optimize your male hormone levels and offset the decline associated with low T.

This is where testosterone boosters come in…

What Are Testosterone Boosters?

Testosterone boosters simply aim to stimulate testosterone production. They don’t contain testosterone themselves but instead provide nutrients that support natural production. It’s like a gentle nudge in the right direction.

They do this by enhancing T production directly or by inhibiting aromatization – as we’ve already mentioned, this is the amount of T that is converted into the female hormone estrogen.

Testosterone boosters are typically a supplement made from natural herbs, minerals or vitamins. Good quality products tend to have minimal added ingredients and are completely legal as they don’t contain testosterone or any other banned substances.

Do They Work?

Its easy to feel quite sceptical about using testosterone boosters.

But anyone who has low T, is over thirty years old or wants to increase androgen levels in a safe way can benefit from this type of supplement. They do work – if you choose the right product.

Physicians will often discuss testosterone replacement therapy (TRT) as an alternative way of elevating your T, however there are a number of side effects that can occur with this type of therapy. It’s the same for patches and gels too.

Whilst there’s no doubt that some of these drugs do in fact elevate male hormone levels, they are strongly linked to prostate cancer and other serious adverse effects.

Testosterone boosters are unique in that they use only natural ingredients to stimulate and optimize testosterone in a way that limits these side effects. And if you choose the the right nutrients and follow the instructions, the side effects are pretty much non-existent.

Choosing the Right Ingredients

The key to finding testosterone boosters that’ll work for you is to focus on the individual contents. Read independent reviews to get an idea of quality, and above all else only choose supplements that use natural ingredients. That way you minimize side effects and boost the chances of it working.

Proprietary Blends

Good quality supplements are always open and honest about the ingredients they use, as well as the specific quantities as well.

For any supplement, the FDA require that all ingredients and amounts are labelled clearly – unless that supplement is a ‘proprietary blend’. This means that if its a blend you don’t know what you’re getting.

Any manufacturer that goes out of their way to not disclose their product content has something to hide, so if it doesn’t disclose it’s ingredient amounts then simply just avoid it – you don’t know what you’re getting.

Common Ingredients in Testosterone Boosters

Now where it gets tricky is the actual ingredients that are included. Some ingredients will boost male hormone levels whereas others may not, but a good testosterone booster has a well-researched and balanced profile of complimentary nutrients.

If you do your research you’ll find that there are hundreds of different nutrients used across a wide range of testosterone boosting products. It can be daunting but don’t let that alarm you.

In order to help you as much as possible, here is an outline of the main ingredients you should look for – or avoid.

Vitamin D3

This fat soluble vitamin is actually a type of steroid hormone, much like an androgen. It regulates the amount of calcium in skeletal muscle tissue and protects against heart disease as well as immune system, respiratory and infectious disorders.

The male reproductive tract is a big target tissue for D3 and this means that optimizing the amount in you body will help to stimulate testosterone production.

Vitamin D is considered one of the gold-standard T-booster ingredients and a number of research studies back this up.

One study for example [1] found that when men supplemented their diet with 3,332 IUs of the nutrient, free and total testosterone levels increased significantly.

D-Aspartic Acid

This amino acid is a fantastic nutrient for anyone wanting to boost T levels, muscle mass or growth hormone production. It is formed via a converting enzyme called aspartate racemase. 

D-aspartic acid plays a key role in regulating luteinizing hormone – the all-important precursor to testosterone. It essentially tells the brain to start producing more T.

According to research studies, DAA is one of only a handful of clinically effective components of testosterone boosters.

It’s technically a non-essential amino acid meaning that your body can manufacture it itself. Although you can make your own and you’ll find DAA in meat and cheese, clinical trials have found that supplementing it can greatly enhance androgen production.

A study by D’Aniello et al [2] found that 90 days of the amino acid was enough to raise serum T levels by 30-60% and semen count by 60-100%.

Coleus Forskohlii

‘Forskolin’ is a Sri Lankan tropical plant with vibrant blue spires. As with many natural herbs it contains a range of bioactive compounds.  In this case the compound is cyclic adenosine monophosphate (cAMP) – an important chemical that can increase the uptake of fatty acids in the body.

It has gained popularity over the last few years as a supposed fat burner and T booster but like with many herb extract science doesn’t quite back up the claims. The only study that shows any positive effect was conducted on overweight and obese volunteers [3].

In the study, each participant was given a high dose of 250 mg of coleus twice per day for 12 weeks. The research team reported that there was a ‘trend’ for testosterone to increase – as high as 34% in some. The problem was though that there was a high variability between participants and the actual change in serum total T concentration was not significantly different amongst groups. 

Other than that you’ll be hard pushed to find any other good studies on this herb. Approach it with caution.

Horny Goat Weed

This epimedium herb has been used as a traditional Asian medicine for hundreds of years. It’s most well know bioactive compound is icariin – a supposed aphrodisiac.

Marketed as a sexual stimulant, horny goat week is reported to stimulate the Leydig cells to produce more testosterone. It is also claimed to increase blood flow to the penis and reduce cortisol levels – a stress hormone that blunts the effects of androgens.

The problem is though that all of these benefits are anecdotal and there’s very little clinical evidence to back this up. In fact studies such as the one published in the Asian Journal of Andrology [4] showed no benefit at all.


As a nutrient that most people don’t get enough of, magnesium helps you to maintain optimal muscle and nerve function. It also helps you regulate your blood sugar levels and maintain elevated protein synthesis – an important part of muscle growth.

A study that supplemented magnesium in both sedentary and active subjects for a 4-week period saw testosterone levels rise significantly [5]. Both free and total T levels rose with regular intake.

This is a great mineral and should form part of your testosterone booster nutrient profile.


Similar to magnesium, zinc is another mineral with male hormone boosting properties. It has antioxidant properties and helps to support your immune system too. It also helps to regulate enzyme reactions so ensures smooth running of your body.

As an athlete that trains hard you’ll lose a lot of zinc through your sweat. Supplementing this nutrient is important for not only health but physical performance as well.

Zinc has been shown to act as an aphrodisiac and T booster in a number of studies. It has been shown in a group of elite wrestlers to preserve T levels during periods of intense exercise [6] and elevate circulating T levels in infertile men with hypogonadism [7].

In large doses it can act as a potent aromatase inhibitor too and can therefore reduce circulating estrogen levels.

Tribulus Terrestris

This spine covered, medicinal herb has been used in both Chinese and Indian medicine for centuries. It contains a number of bioactive compounds such as steroidal saponins and other adaptogens that affect the way the body works.

Back in the 1970s this herb was popular amongst Bulgarian weightlifters and athletes as a strength and athleticism booster. It was also claimed to enhance testosterone production and increase lean muscle mass.

The problem is though that there’s not really much evidence that backs these claims up. Studies have shown that even at high doses this herb doesn’t offer much benefit to hormone stimulation. Science just doesn’t back up the claims.

Neychev et al [8] for example found that when 21 trained males were given 10-20 mg per kg of the herb, steroidal saponins neither directly nor indirectly elevated T levels.

These results were echoed in a similar study published in the International Journal of Sports Nutrition and Exercise Metabolism, this time using 15 well trained male volunteers [9] .

You also need to know that there a number of side effects attributed to tribulus use. These include abdominal discomfort, nausea and gas. It can also interact with other medications such as those used for blood pressure or diabetes as well.

Anyone who has a metabolism or hormone-dependant illness should avoid it altogether.


Popular in Asian culture and cuisine, fenugreek is a spice herb that has been found to enhance libido, optimize body composition and promote free testosterone.

It is a bitter tasting herb that is high in nutrients such as alkaloid compounds, vitamin C and folic acid. Its nutrient profile plus high fiber content has been used to treat both type 1 and type 2 diabetes as well as those with high cholesterol.

Fenugreek reduces blood sugar and as such reduces levels of SHBG – remember, this specific protein binds up testosterone making it unusable. If you can reduce SHBG levels then you’re on to a winner as free T levels can increase without getting swallowed up by binding proteins.

One study found that when 30 trained men were given 500 mg of fenugreek, their total and bioavailable T levels rose significantly [10]. Not only that but their body composition improved too.

Bulbine Natalensis

Bulbine is a South African herb that is characterized by its yellow spiked, star-shaped flowers. As a natural herb it contains a range of alkaloids, glycosides and saponins.

It is claimed that these bioactive compounds stimulate the release of gonadotropin-releasing hormone (GnRH) – the master switch for T production.

The problem with this supplement though is that there’s very little actual clinical research to back up the claims. To date there’s only been one human study that has assessed its safety – and that was classed as a’first step’ clinical trial just to get the ball rolling.

In the research, 36 men were given 650 mg of the herb over a 28-day period [11]. The results were worrying. There was a statistically significant rise in alkaline phosphatase – an enzyme that regulates protein breakdown. There were also a number of other side effects too.

Since then, additional research has found the supplement to be not completely safe after selective toxicity was found in the liver and kidneys of study subjects [12].

GMP Certification and Testosterone Boosters

Good manufacturing practice or GMP is a system used in the supplement industry. It ensures that products are consistently produced and conform to expected quality standards. Ultimately, it’s a good way to ensure that pharmaceutical production is safe and all necessary precautions have been taken to minimize risks to your health.

Always look out for testosterone boosters that have been manufactured in a current GMP facility. These sites are approved and enforced by FDA regulations and ensures top quality products.

If you don’t purchase directly from cGMP regulated sites then you run the risk of sub-par quality products. Your safety has to come first, so by ensuring the proper manufacturing processes you are taking all of the necessary precautions.


  1. Pilz, Effect of vitamin D supplementation on testosterone levels in men. Horm Metab Res. 2011; 43(3): 223-5
  2. D’Aniello et al, G. D-aspartate, a key element for the improvement of sperm quality. Adv. Sex. Med. 2012; 2: 47–53
  3. Godard, MP et al. Body composition and hormonal adaptations associated with forskolin consumption in overweight and obese men. Obes Res. 2005; 13(8): 1335-43
  4. Zhang, ZB et al. The testosterone mimetic properties of icariin. Asian J Androl. 2006; 8(5): 601-5
  5. Cinar, V et al.. Effects of magnesium supplementation on testosterone levels of athletes and sedentary subjects at rest and after exhaustion. Biol Trace Elem Res.2011;140:18–23
  6. Kilic, M et al. The effect of exhaustion exercise on thyroid hormones and testosterone levels of elite athletes receiving oral zinc. Neuro Endocrinol Lett. 2006; 27(1-2): 247-52
  7. Netter, A et al. Effect of zinc administration on plasma testosterone, dihydrotestosterone, and sperm count. Arch Androl. 1981; 7(1): 69-73
  8. Neychev, VK et al. The aphrodisiac herb Tribulus terrestris does not influence the androgen production in young men. J Ethnopharmacol. 2005; 101: 319-323
  9. Antonio, J et al. The effects of Tribulus terrestris on body composition and exercise performance in resistance-trained males. Int J Sport Nutr Exerc Metab. 2000 Jun;10(2):208-15
  10. Wilborn, C et al. Effects of a purported aromatase and 5α-reductase inhibitor on hormone profiles in college-age men. Int J Sport Nutr Exerc Metab. 2010; 20(6):457-65
  11. Hofheins, JE et al. Short term safety of bulbine natalensis supplementation in healthy men. Journal of the International Society of Sports Nutrition. 2012; 9(Suppl 1): 33
  12. Afolayan, AJ et al. Effect of Bulbine natalensis Baker stem extract on the functional indices and histology of the liver and kidney of male Wistar rats. J Med Food. 2009; 12(4): 814-20