Top Three Testosterone Boosters

Your guide to the safest and most powerful testosterone boosters on the market right now

The best testosterone boosters could help you:

  • Increase muscle mass
  • Become stronger
  • Build stamina
  • Boost your sex drive
  • Lift your mood
  • Increase your confidence

Sounds great, doesn’t it? But with so many products all claiming to do the same thing, how do you know which one is right for you? After all, some testosterone boosters may not deliver the results they promise.

But as long you know where to look, the right product can help you achieve all the benefits above – without nasty side effects or risks to your health.

And that’s why you’re here, right? We’ve put hundreds of these testosterone boosters through their paces to make it easy for you to find the best one(s) for your needs. And we’ve narrowed the list down to just three great products…

Top Test Boosters#1 Hunter Test#2 TestoFuel#3 Prime Male
Hunter Testtestofuelhomepage1prime-male-table1
Overall User Rating5starstable4.5stars4starstable
Supplement WebsiteVisit siteVisit siteVisit site
Capsules Per Day644
Ships toWorldwideWorldwideWorldwide
Company ReputationGreatExcellentGood
Guarantee3 months (on selected purchases)90 Days
(With 3 box deal)
3 months
(on selected purchases)
Supports Testosterone ProductionYes – 5/5Yes – 4.5/5Yes – 4/5
Promotes Free TestosteroneYes – 5/5Yes – 4.5/5Yes – 4/5
Increases Energy LevelsYes – 5/5Yes – 4.5/5Yes – 4/5
Price$75.00$65.00 (Discounts on multiple boxes)$69.00
Side effectsNone reportedNone reportedNone reported
Read Full ReviewRead ReviewRead ReviewRead review
Hunter Test5starstableVisit Site6WorldwideGreat3 months (on selected purchases)Yes – 5/5Yes – 5/5Yes – 5/5$75.00 (Discounts on multiple boxes)None reportedRead review
testofuelhomepage14.5starsVisit Site4WorldwideExcellent90 Days (With 3 Box Deal)Yes – 4.5/5Yes – 4.5/5Yes – 4.5/5$65.00 (Discounts on multiple boxes)None reportedRead review
prime-male-table14starstableVisit Site4WorldwideGood3 months (on selected purchases)Yes – 4/5Yes – 4/5Yes – 4/5$69.00None reportedRead review

What we look for in a testosterone booster

Buzz around the product

The supplement industry is always changing and improving. This means what was once our #1 product can slide down the pecking order in a matter of months. To give you the most precise information, we take care to stay up to date with new research and innovations.

We scour forums, read magazines, check out other reviews and subscribe to newsletters in search of new and exciting testosterone boosters to test. We also listen to our readers’ suggestions – so let us know if there are any testosterone-boosting supplements you’d like us to review.

Company reputation

The manufacturer’s reputation, its existing product line and customer reviews are usually – but not always – key signs of how good a testosterone booster is.

Performance

With a smart blend of key science-backed nutrients, the best products can improve the way you look and feel in a matter of months. To help you find the best product for your needs, we ignore marketing hype. Instead, we use the latest research from respected scientific journals to put each ingredient and dosage under the microscope.

Side effects and safety

While there are great testosterone boosters out there, many products still contain ingredients that risk your health and/or cause side effects. By contrast, the supplements on this list are 100% natural and are highly unlikely to induce discomfort or do you any harm.

Proprietary blends

A big part of our ability to assess safety and quality depends on a product’s use of proprietary blends. These are sub-formulas that display ingredients, but the not the exact amount of each nutrient.

Some manufacturers use proprietary blends to hide ineffective or potential harmful formulas. Such products can raise the risk of side effects and are not worth your money.

To ensure you know exactly what you’re buying, all the testosterone boosters on this list ignore proprietary blends in favor of clear, honest lists of ingredients.

Value

Is the manufacturer cutting corners to save money, or have they spared no expense to create the perfect formula? To assess the value of a product, we look at everything from our personal results, to the quality of the formula, ingredient volume, serving sizes and number of capsules.

1. Hunter Test

Official website: www.hunterlife.com/hunter-test

Hunter Test is a premium product designed for the busy man who wants more success in every part of his life – whether at home, at work, or in the gym.

This testosterone booster is part of a “suite” of supplements from the Hunter brand. This range also includes Hunter Burn (fat burner) and Hunter Focus (nootropic).

When we tried Hunter Test, we were surprised to find it delivers everything it promises. And having read plenty of other glowing reviews and feedback from our readers, it’s clear we’re not alone in the belief that Hunter Test is the #1 testosterone booster on the market.

Why you’ll like Hunter Test:

  • Gives you more energy – Get more done and enjoy your life more.
  • Raises your libido – Enjoy sex more and improve your relationships
  • Enhances your drive and motivation – Be more proactive, hit your goals and overcome setbacks.
  • Lifts your confidence – Gain more self-belief and “command respect in every room”.
  • Protects your long-term health – Safe, natural ingredients help you live a longer, more comfortable, happier life.

How does it work?

Hunter Test’s main strength lies in the sheer quality of its formula. And there are many things that make it a better product – including the high quality of the ingredients and their dosages.

But what really sets apart are the serving sizes and number of capsules. Whereas standard products offer a monthly supply of just 120 capsules per bottle, Hunter Test provides 180. This amounts to six capsules per day, rather than the standard four.

The marketing for Hunter Test claims this creates a more powerful product that “reverses testosterone decline” and helps you “reclaim your masculinity”. And while we didn’t measure our testosterone levels before or after our review of Hunter Test, we can say it made us look and feel better than we had in years.

Is Hunter Test safe?

As an all-natural product, Hunter Test is safe to use and won’t cause side effects (unless you’re allergic to any of its contents).

Its nine ingredients are some of the best-researched we’ve seen in a testosterone booster.

We’ve also scoured the available research, and it’s clear each ingredient is dosed to more or less optimal amount – but still well below the tolerable upper intake level (UL).

What’s more, Hunter Test doesn’t contain any artificial colors, flavors, or preservatives. It’s even free from GMO, soy and gluten.

Hunter Test is also made at FDA and cGMP-approved facilities in the US and UK. This ensures the product remains free of contaminants – and stays safe.

Hunter-Test-ingredients

How should I take Hunter Test?

The directions on the bottle suggest taking two capsules with a full glass of water three times per day. We took ours with every main meal – and it worked well.

Ingredients

Vitamin D3: Research shows this steroid sex hormone may raise testosterone by an average of 20% over the course of one year [1]. It’s also shown to strengthen bones [2], increase muscle mass [3], and lower the risk of diabetes [4] and heart disease [5]. 5000 IU is the dose recommended by the Vitamin D Council [6], so it’s great to see an optimal amount of D3 in Hunter Test.

D-aspartic acid (D-AA): In one study, this amino acid increased testosterone by 30-60% after 90 days of use [7]. D-AA has also been shown to boost sperm counts by up to 100%. Alongside D3, it also improves users’ sense of well-being and libido [8]. Hunter Test gives you 30% more D-AA than our #2 pick (3000mg vs 2300mg), making it much more powerful.

Ashwagandha: This herb’s name comes from the Sanskrit for “smell of horse” – as legend has it, taking ashwagandha can make you as “strong as a horse”. The adaptogen boosts testosterone [9] and lifts your mood [10], while also reducing fatigue [11] and making you stronger.

Indole-3-carbinol (I3C): This androgen inhibitor stops your body turning excess testosterone into estrogen (the female hormone) [12]. This increases your anabolic potential to help you build muscle [13]. By balancing your hormones, I3C also helps stop you putting on weight [14] or developing the dreaded man-boobs.

Price

Hunter Test is available in four different currencies:

US dollars ($ – USD):

  • One bottle (one month’s supply) – $75
  • Two bottles (two months’ supply) – $150 (free US shipping)
  • Three bottles + one free bottle (four months’ supply) – $225 (with free US and UK shipping)

GB pounds sterling (£ – GBP):

  • One bottle (one month’s supply) – £55
  • Two bottles (two months’ supply) – £110 (free UK shipping)
  • Three bottles + one free bottle (four months’ supply) – £165 (with free US and UK shipping)

Australian dollars ($ – AUD):

  • One bottle (one month’s supply) – $100
  • Two bottles (two months’ supply) – $200
  • Three bottles + one free bottle (four months’ supply) – $300

Euros (€ – EUR):

  • One bottle (one month’s supply) – €60
  • Two bottles (two months’ supply) – €120
  • Three bottles + one free bottle (four months’ supply) – €180

Are there any guarantees or promotions?

When you buy a 90-day supply (or more) of Hunter Test, you qualify for the brand’s 90-day guarantee. This means you can ask for a refund if you’re not happy with your purchase after three months.

By now, you can tell we love Hunter Test – but are there any downsides?

  • Premium price – At $75 per bottle, it’s the most expensive testosterone booster on this list
  • Not suitable for vegetarians – uses gelatin capsules
  • Only available from the official website: www.hunterlife.com/hunter-test

The final word on Hunter Test

If you’re busy, ambitious and willing to pay a higher price to get the best testosterone booster out there, Hunter Test is for you.

Research shows every one of its nine ingredients boost testosterone. It also gives users a host of other benefits – from a higher sex drive, to increased muscle mass and energy. While Hunter Test contains some of the same ingredients as TestoFuel (our #2 pick), it also uses higher doses and larger serving sizes.

Why does this matter?

Because it makes Hunter Test the most powerful testosterone booster we’ve ever used. Meanwhile, the natural, science-backed formula also makes it not just potent, but safe to use. The quality and attention to detail here is outstanding.

Hunter Test may cost a little more than standard testosterone boosters – but it’s worth every penny.

Our score: 5/5

Buy Hunter Test here

or

Read our Hunter Test review

2. TestoFuel

Official website: www.testofuel.com

TestoFuel is a popular testosterone booster from Roar Ambition, a specialist supplement company based in the UK.

Roar Ambition also makes and sells 4 Gauge (pre-workout) and Instant Knockout (fat burner), but we’re told this testosterone booster is its best-selling product. In fact, TestoFuel has customers in 178 countries across the globe.

TestoFuel also boasts positive feedback on YouTube, on bodybuilding forums and on review sites.

Although aimed at a younger men looking to build more muscle, TestoFuel contains ingredients that are suitable for everyone. It’s even endorsed by 70-year-old bodybuilding legend Robby Robinson.

Why you’ll like TestoFuel:

  • Build more muscle – Testosterone is one of the main building blocks of growth.
  • Increase strength – Powerful formula gives you all the nutrients you need in just one bottle.
  • Lower your body fat – Achieve ripped abs and gain that coveted V-shaped torso.
  • Gain more energy and drive – Build a winning mentality and become more confident.
  • Boost your sex drive – Satisfy your partner every time.

How does it work – and is it safe?

TestoFuel uses a 100% natural formula, with key nutrients that are both potent and safe. It’s designed primarily to help you make more gains in the gym and boost your sex drive without harmful steroids or hormones.

Will you pass a drugs test for competition?

The use of all-natural nutrients means you’ll also pass a drugs test while taking TestoFuel, while the lack of harsh chemicals means there’s no need to cycle it.

What’s more, this testosterone booster is dosed and prepared to strict FDA and cGMP guidelines in both the USA and UK. This ensures the product is subject to the highest standards of testing and cleanliness at every stage of production.

TestoFuel contains ingredients that stimulate the release of the Luteinizing hormone – a major testosterone precursor.

It also inhibits the sex-hormone binding globulin (SHBG) to help restore your testosterone’s anabolic power and enhance your sex drive. According to the TestoFuel website, this product’s ingredients have been proven to boost testosterone by 40% in a study by the National Institutes of Health.

testofuel-ingredients

How to take TestoFuel

Each bottle of TestoFuel contains 120 capsules, which gives you a serving size of four capsules per day. According to the TestoFuel blog, you should take your capsules “evenly” throughout the day.

However, it works just as well when you take two capsules with your breakfast and two with your lunch or dinner. The lack of a strict serving schedule is one of the great things about natural products like this.

Ingredients

Vitamin D3: More of a steroid hormone than a vitamin, D3 plays a vital role in your body’s ability to produce testosterone [15] and build muscle mass [16]. In one study, men who took D3 for 12 months increased their levels of the male hormone by 20% on average. TestoFuel contains a dose of 5000 IU, which is the amount the Vitamin D Council recommends to those suffering from a deficiency of the nutrient [17].

D-aspartic acid (D-AA):  An amino acid, D-AA is shown to increase testosterone [18] and sex drive [19], while also lifting your mood.

Oyster extract: Oyster extract contains 59 trace elements which are vital to your health. It is richest known source of zinc, which research suggests could boost testosterone by up to 84% [20].

Asian red Panax ginseng: This herb stimulates the two main sex-hormone receptors [21] to increase the libido and raise testosterone.

What do others think of TestoFuel?

Paul transformed his body in just four months…

Paul-TestoFuel-testimonial

Jake says he gained 13 pounds of muscle with TestoFuel:

Josh noticed his energy and motivation rise after just two weeks using TestoFuel…

Josh-TestoFuel-testimonial

Price

TestoFuel is available in four different currencies:

US dollars ($ – USD):

  • One bottle (one month’s supply) – $65
  • Two bottles (two months’ supply) – $130 (free US and UK shipping)
  • Three bottles + one free bottle (four months’ supply) – $195 (with free worldwide shipping)

GB pounds sterling (£ – GBP):

  • One bottle (one month’s supply) – £39
  • Two bottles (two months’ supply) – £78 (free UK and US shipping)
  • Three bottles + one free bottle (four months’ supply) – £117 (with free worldwide shipping)

Australian dollars ($ – AUD):

  • One bottle (one month’s supply) – $85
  • Two bottles (two months’ supply) – $170
  • Three bottles + one free bottle (four months’ supply) – $255 (with free worldwide shipping)

Euros (€ – EUR):

  • One bottle (one month’s supply) – €45
  • Two bottles (two months’ supply) – €90
  • Three bottles + one free bottle (four months’ supply) – €135 (with free worldwide shipping)

Value for money

With its lower doses and serving sizes, TestoFuel is not as powerful Hunter Test (our #1). But it also contains some of the same key ingredients (D3, D-AA and more) for a lower price. This makes TestoFuel exceptional value for money.

Are there any guarantees or promotions?

Like Hunter Test, TestoFuel is subject to a generous 90-day guarantee. When you buy a three bottles (three months’ worth) or more, you qualify for a refund if you’re not satisfied with your purchase.

TestoFuel is a great product – but are there any downsides?

  • Not as potent as Hunter Test – lower doses and serving sizes
  • Unsuitable for vegetarians – uses animal-based capsules
  • Only available from product website: testofuel.com

Why isn’t it #1?

The TestoFuel formula isn’t quite as powerful as Hunter Test, with key ingredients like D-AA slightly underdosed. TestoFuel also lacks ashwagandha and indole-3-carbinol – two great additions to the Hunter Test formula which ensure the newer product stands above the rest.

Final word on TestoFuel

TestoFuel is packed full of proven testosterone-boosting ingredients. And it’s similar to our favorite testosterone booster in many ways.

And while it may not be as powerful as Hunter Test, TestoFuel’s lower price makes it a great everyman product. It’s particularly good for helping you build muscle in the gym.

Our score: 4/5

Buy TestoFuel here

or

Check out our full TestoFuel review

3. Prime Male

Official website: www.primemale.com

Prime-Male-box-bottle-pills

Prime Male is a 100% natural testosterone booster from Propura – and it’s the company’s flagship product.

It contains many of the same ingredients as TestoFuel (our #2), but with some dose differences and the removal/addition of certain nutrients.

What you’ll like about Prime Male:

  • Build lean muscle – Become the strong, healthy guy you were in your 20’s.
  • Shed excess weight – Prevent excess belly fat and man-boobs.
  • Boost your energy levels – Avoid or reduce the fatigue that comes with a drop in testosterone.
  • Lift your mood – Feel happier and more confident.
  • Look after your long-term health – lower your risk of diabetes, heart disease and brittle bones.

How does Prime Male work – and is it safe?

Whereas most products of this kind are designed to help gym users build muscle, Prime Male helps men over 30 deal with the problem of falling testosterone that comes as we age.

The Prime Male formula is designed to “turn back the clock on male aging”.

It achieves this with 12 all-natural nutrients that work together to prevent your body from turning testosterone into estrogen, which in turn could lead to excess body fat and muscle wastage. The formula also helps maintain heart health and prevent high blood pressure. It even helps you avoid insulin resistance, which could lead to the onset of diabetes.

As a 100% natural testosterone booster, Prime Male is safe to use and is unlikely to cause any adverse side effects. It’s also fair to say Prime Male is a much cleaner and safer option than testosterone replacement therapy (TRT), which can raise the risk of blood clots and strokes [22].

prime_male_ingredients

How to take Prime Male

Each bottle of Prime Male contains 120 capsules, which gives you a daily serving of four capsules per day over 30 days.

According to the directions for use, you should take one capsule four times per day.

Ingredients

Vitamin D3: Vitamin D deficiency is linked to low testosterone [23]. As low levels of vitamin D are more common in older people [24], it’s important for men over 30 to get their fill. D3 supplementation has been shown to reverse the signs of low testosterone, such as weight gain, muscle wastage [26] and loss of libido [27].

D-aspartic acid (D-AA): One study showed this amino acid increased testosterone by 42% in 12 days [28]. As men’s testosterone drops by an average of 1% per year, this means that D-AA can help you reverse 42 years of testosterone loss in a little under 2 weeks!

Mucuna pruriens: A natural source of L-DOPA, mucuna pruriens is shown to boost testosterone in infertile men [29].

Nettle root: Nettle root (or stinging nettle) contains lignans which are said to inhibit the sex-hormone binding globulin (SHBG) [30] to allow free flow of testosterone in your system.

What other guys think of Prime Male

Rocky IV actor Dolph Lundgren says Prime Male helps him stay in shape as he gets older…

Maxx calls Prime Male “the best testosterone booster ever”:

Jake says Prime Male improves his performance in the gym and in the bedroom…

 

Price

 

Prime Male is available in three different currencies:

US dollars ($ – USD):

  • One bottle (one month’s supply) – $69
  • Two bottles (two months’ supply) – $138 (free US and UK shipping)
  • Three bottles + one free bottle (four months’ supply) – $207 (with free worldwide shipping)

GB pounds sterling (£ – GBP):

  • One bottle (one month’s supply) – £39
  • Two bottles (two months’ supply) – £78 (free UK and US shipping)
  • Three bottles + one free bottle (four months’ supply) – £117 (with free worldwide shipping)

Euros (€ – EUR):

  • One bottle (one month’s supply) – €49
  • Two bottles (two months’ supply) – €98
  • Three bottles + one free bottle (four months’ supply) – €147 (with free worldwide shipping)

Does Prime Male come with a guarantee?

Just like Hunter Test and TestoFuel, Prime Male comes with a 90-day risk-free guarantee. This means that when you buy three bottles (or more) of Prime Male, you have the right to return the product for refund if you’re not satisfied with your results.

Any downsides?

  • Less potent than Hunter Test or TestoFuel in some respects – not as much D-AA as we’d like.
  • Contains one unproven ingredient – Nettle root isn’t backed by as much research as other nutrients in the formula.
  • Non-vegetarian – Prime Male uses gelatin capsules.
  • Costs more than TestoFuel – You pay more money for a product with a more limited appeal.
  • Fewer currency options – Prime Male is not available in Australian dollars.

Final word on Prime Male

There’s no doubt Prime Male is one of the best testosterone boosters around. The difference between this and TestoFuel is slight, but significant.

Prime Male contains less D-aspartic than we’d prefer, while mucuna pruriens isn’t one of our favorite testosterone-boosting ingredients – and it’s not backed as much scientific research as we’d like.

That said, Prime Male is designed specifically to help men over 30 reverse the distressing signs of male aging – which makes it unique among the best natural testosterone boosters on the market.

What’s more, Prime Male is effective – and a much safer alternative to testosterone replacement therapy (TRT).

Score: 4/5

Buy Prime Male here

or

Read our Prime Male review

Summary

So there you have it – three awesome testosterone boosters. All are great choices – and each one contains all-natural ingredientsand is safe to use.

TestoFuel or Prime Male?

Prime Male aims to help older men “turn back the clock on make aging”, is scientifically backed and thoroughly researched.

TestoFuel is aimed at younger men – and it works well as a means to enhance muscle gains in the gym. But it’s mix of great ingredients at a more affordable price make it a slightly better prospect for a broad range of users when compared to Prime Male.

Why Hunter Test is the best

 

However, the guys behind Hunter Test left no stone unturned in their drive to create the perfect testosterone booster. And it’s more or less there, with spot-on amounts of must-have ingredients.

Meanwhile, the shrewd additions of ashwagandha and indole-3-carbinol make Hunter Test that much better than any other testosterone booster we’ve ever tried.

With this in mind, there can be only one winner in our battle of the testosterone boosters:

Hunter Test

Hunter-Test-four-bottles

To find out more, or to buy Hunter Test, click here

References

  1. Pilz, S. et al. Effect of vitamin D supplementation on testosterone levels in men. Horm Metab Res. 2011;43(3):223–225
  2. Laird, E. et al (2010). Vitamin D and Bone Health; Potential Mechanisms. Nutrients, 2(7), pp.693-724.
  3. Tomlinson, P.B. et al. Effects of vitamin D supplementation on upper and lower body muscle strength levels in healthy individuals. A systematic review with meta-analysis. J Sci Med Sport. 2015 Sep;18(5):575-80.
  4. Talaei, A. et al (2013). The effect of vitamin D on insulin resistance in patients with type 2 diabetes. Diabetology & Metabolic Syndrome, 5(1), p.8.
  5. Moretti, H. et al (2017). Vitamin D3 repletion versus placebo as adjunctive treatment of heart failure patient quality of life and hormonal indices: a randomized, double-blind, placebo-controlled trial. BMC Cardiovascular Disorders, 17(1).
  6. Vitamin D Council. (2018). Comparing 2,000 IU/day vs. 5,000 IU/day vitamin D supplementation. [online] Available at: https://www.vitamindcouncil.org/comparing-2000-iuday-vs-5000-iuday-vitamin-d-supplementation/ [Accessed 11 Oct. 2018].
  7. D’Aniello, S. et al. D-aspartate, a key element for the improvement of sperm quality. Adv. Sex. Med. 2012; 2: 47–53
  8. Bloomer, R. et al (2015). Influence of a D-aspartic Acid/Sodium Nitrate/Vitamin D3 Dietary Supplement on Physiological Parameters in Middle-aged Men: A Pilot Study. The Open Nutraceuticals Journal, 8(1), pp.43-48.
  9. Wankhede, S. et al. Examining the effect of Withania Somnifera supplementation on muscle strength and recovery: a randomized controlled trial. J Int Soc Sports Nutr. 2015 Nov 25;12:43.
  10. Chandrasekhar, K. et al. A Prospective, Randomized Double-Blind, Placebo-Controlled Study of Safety and Efficacy of a High-Concentration Full-Spectrum Extract of AshwagandhaRoot in Reducing Stress and Anxiety in Adults. Indian J Psychol Med. 2012 Jul-Sep; 34(3): 255–262.
  11. Cooley, K. et al. Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974. PLoS One. 2009 Aug 31;4(8):e6628.
  12. Michnovicz, J.J. et al. Changes in levels of urinary estrogen metabolites after oral indole-3-carbinol treatment in humans. J Natl Cancer Inst. 1997 May 21;89(10):718-23.
  13. Zhao, H. et al (2018). Shift from androgen to estrogen action causes abdominal muscle fibrosis, atrophy, and inguinal hernia in a transgenic male mouse model. Proceedings of the National Academy of Sciences, 115(44), pp.E10427-E10436.
  14. Choi, Y. et al (2012). Indole-3-carbinol prevents diet-induced obesity through modulation of multiple genes related to adipogenesis, thermogenesis or inflammation in the visceral adipose tissue of mice. The Journal of Nutritional Biochemistry, 23(12), pp.1732-1739.
  15. Pilz, S. et al. Effect of vitamin D supplementation on testosterone levels in men. Horm Metab Res. 2011;43(3):223–225
  16. Tomlinson, P.B. et al. Effects of vitamin D supplementation on upper and lower body muscle strength levels in healthy individuals. A systematic review with meta-analysis. J Sci Med Sport. 2015 Sep;18(5):575-80.
  17. Vitamin D Council. (2018). Comparing 2,000 IU/day vs. 5,000 IU/day vitamin D supplementation. [online] Available at: https://www.vitamindcouncil.org/comparing-2000-iuday-vs-5000-iuday-vitamin-d-supplementation/ [Accessed 11 Oct. 2018].
  18. D’Aniello, S. et al. D-aspartate, a key element for the improvement of sperm quality. Adv. Sex. Med. 2012; 2: 47–53
  19. Bloomer, R. et al (2015). Influence of a D-aspartic Acid/Sodium Nitrate/Vitamin D3 Dietary Supplement on Physiological Parameters in Middle-aged Men: A Pilot Study. The Open Nutraceuticals Journal, 8(1), pp.43-48.
  20. Jalali, G. et al (2010). Impact of oral zinc therapy on the level of sex hormones in male patients on hemodialysis. Renal Failure, 32(4), pp.417-419. 
  21. Park, J. et al (2017). Effects of ginseng on two main sex steroid hormone receptors: estrogen and androgen receptors. Journal of Ginseng Research, 41(2), pp.215-221.
  22. Howard LeWine, M. (2019). FDA warns about blood clot risk with testosterone products – Harvard Health Blog. [online] Harvard Health Blog. Available at: https://www.health.harvard.edu/blog/fda-warns-blood-clot-risk-testosterone-products-201406247240 [Accessed 7 Jan. 2019].
  23. Lerchbaum, E. et al (2017). Vitamin D and Testosterone in Healthy Men: A Randomized Controlled Trial. The Journal of Clinical Endocrinology & Metabolism, 102(11), pp.4292-4302.
  24. Boucher, B. (2019). The Problems of Vitamin D Insufficiency in Older People. [online] PubMed Central (PMC). Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3501367/ [Accessed 7 Jan. 2019].
  25. Lerchbaum, E. et al (2017). Vitamin D and Testosterone in Healthy Men: A Randomized Controlled Trial. The Journal of Clinical Endocrinology & Metabolism, 102(11), pp.4292-4302.
  26. Bhat, M., Kalam, R., Qadri, S., Madabushi, S. and Ismail, A. (2013). Vitamin D Deficiency-Induced Muscle Wasting Occurs through the Ubiquitin Proteasome Pathway and Is Partially Corrected by Calcium in Male Rats. Endocrinology, 154(11), pp.4018-4029.
  27. [online]. Available at: https://www.issm.info/news/sex-health-headlines/vitamin-d-important-for-mens-sexual-health-study-finds/ [Accessed 7 Jan. 2019].
  28. Melville, G. et al (2015). Three and six grams supplementation of d-aspartic acid in resistance trained men. Journal of the International Society of Sports Nutrition, 12(1).
  29. Shukla, K., Mahdi, A., Ahmad, M., Jaiswar, S., Shankwar, S. and Tiwari, S. (2010). Mucuna pruriens Reduces Stress and Improves the Quality of Semen in Infertile Men. Evidence-Based Complementary and Alternative Medicine, 7(1), pp.137-144.
  30. Hryb, D. et al (1995). The Effect of Extracts of the Roots of the Stinging Nettle (Urtica dioica) on the Interaction of SHBG with its Receptor on Human Prostatic Membranes. Planta Medica, 61(01), pp.31-32.