Tongkat AliHuman study
Stress and hormone measures with a Tongkat Ali extract
Talbott et al., 2013 · Placebo-controlled study over four weeks
Reported changes in selected mood measures and salivary hormone measures over four weeks compared with placebo.
Limitation. Mixed-sex, small study of a standardized extract. Salivary outcomes and study results cannot be presented as this product’s expected blood-test change.
Read summary
- Design
- Placebo-controlled study over four weeks
- Participants
- 63 moderately stressed adults, mixed sex
- Measured outcome
- Mood measures and salivary hormone measures
- Relevance to this formula
- The Tongkat Ali amount and specification in this blend are not disclosed, so equivalence to the studied extract is not established.
- Citation
- Talbott et al., 2013
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AshwagandhaHuman study
Perceived stress with an ashwagandha root extract
Chandrasekhar et al., 2012 · Randomized, placebo-controlled trial over 60 days
Reported lower stress scores and serum cortisol with a specific root extract than with placebo.
Limitation. Particular extract and population. No dose or form equivalence to this blend is established. The same changes or timeline are not promised.
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- Design
- Randomized, placebo-controlled trial over 60 days
- Participants
- 64 adults with chronic stress
- Measured outcome
- Stress scores and serum cortisol
- Relevance to this formula
- The ashwagandha amount in this blend is not provided, and a 25:1 descriptor does not establish equivalence to the studied extract.
- Citation
- Chandrasekhar et al., 2012
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AshwagandhaHuman study
Strength and recovery during resistance training
Wankhede et al., 2015 · Randomized, placebo-controlled trial alongside a resistance-training program
Reported improvements in strength and selected recovery and body-composition measures relative to placebo.
Limitation. Training was part of the intervention. Muscle gain, fat loss, or exercise-free results are not promised from this formula.
Read summary
- Design
- Randomized, placebo-controlled trial alongside a resistance-training program
- Participants
- Men following a resistance-training program
- Measured outcome
- Strength, recovery markers, and body-composition measures
- Relevance to this formula
- The study tested a specific extract with a training program, not this combined formula.
- Citation
- Wankhede et al., 2015
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ShilajitHuman study
Testosterone measures with purified shilajit
Pandit et al., 2016 · Placebo-controlled study over 90 days
Reported changes in testosterone measures over 90 days compared with placebo.
Limitation. Purified study preparation with no matching specification or individual amount established here. This does not show that the formula corrects low testosterone.
Read summary
- Design
- Placebo-controlled study over 90 days
- Participants
- Healthy men aged 45 to 55
- Measured outcome
- Testosterone measures
- Relevance to this formula
- The shilajit in this blend has no published specification or disclosed amount.
- Citation
- Pandit et al., 2016
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ShilajitHuman study
Strength retention after a fatigue protocol
Keller et al., 2019 · Controlled study using a laboratory fatigue protocol
Examined strength retention following a laboratory fatigue protocol using a particular shilajit preparation.
Limitation. Exercise fatigue is a different endpoint from all-day energy, afternoon tiredness, or chronic fatigue. This is not an energy guarantee.
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- Design
- Controlled study using a laboratory fatigue protocol
- Measured outcome
- Strength retention after fatiguing exercise
- Relevance to this formula
- A particular preparation was studied; equivalence to the shilajit in this blend is not established.
- Citation
- Keller et al., 2019
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MacaHuman study
Self-reported sexual desire in adult men
Gonzales et al., 2002 · Randomized, placebo-controlled trial over 12 weeks
Found improved self-reported desire without a corresponding difference in testosterone versus placebo.
Limitation. Desire is not the same outcome as testosterone. The studied preparation cannot be assumed equivalent to the 40:1 ingredient described here.
Read summary
- Design
- Randomized, placebo-controlled trial over 12 weeks
- Participants
- Adult men
- Measured outcome
- Self-reported sexual desire and serum testosterone
- Relevance to this formula
- The maca amount in this blend is not disclosed, and the study did not measure this formula.
- Citation
- Gonzales et al., 2002
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FenugreekHuman study
A specialized fenugreek seed extract in men
Rao et al., 2016 · Randomized, placebo-controlled trial
Studied a specialized fenugreek seed extract for androgen-related symptoms, hormone measures, and sexual function.
Limitation. The supplied formula is not identified as containing that branded extract. Its brand name is not a product ingredient here, and its claims do not transfer.
Read summary
- Design
- Randomized, placebo-controlled trial
- Measured outcome
- Androgen-related symptoms, hormone measures, and sexual function
- Relevance to this formula
- The fenugreek in this blend has no disclosed specification or amount.
- Citation
- Rao et al., 2016
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Fadogia AgrestisAnimal research
Testicular-function measures in male rats
Yakubu et al. · Animal research
Evaluated testicular-function measures in male rats given a Fadogia Agrestis extract.
Limitation. Animal research. It does not establish human benefit, a safe human amount, or long-term safety.
Read summary
- Design
- Animal research
- Participants
- Male rats
- Measured outcome
- Testicular-function measures
- Relevance to this formula
- No human evidence for this ingredient is included here.
- Citation
- Yakubu et al.
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BoronIngredient overview
Boron: health-professional fact sheet
NIH Office of Dietary Supplements · Ingredient overview, not a clinical trial
Summarizes what is known about boron and where the evidence stands.
Limitation. Background reading on the trace element, not a trial of this product.
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- Design
- Ingredient overview, not a clinical trial
- Measured outcome
- Summary of boron intake, sources, and research
- Relevance to this formula
- Boron’s presence does not establish a free-testosterone result from this formula.
- Citation
- NIH Office of Dietary Supplements
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Horny Goat WeedAnimal research
Icariin, a purified Epimedium compound, in rats and cell cultures
Shindel et al., 2010 · Animal and laboratory research
Reported effects of purified icariin on penile blood-flow measures and nerve-tissue markers in injured rats and in cultured nerve cells.
Limitation. Animal and laboratory research on a single purified compound. It does not establish a sexual-function benefit, a safe human amount, or long-term safety.
Read summary
- Design
- Animal and laboratory research
- Participants
- Rats with cavernous-nerve injury; cultured pelvic ganglia
- Measured outcome
- Penile blood-flow measures and nerve-tissue markers
- Relevance to this formula
- The Horny Goat Weed in this blend is a whole-herb ingredient with no disclosed icariin content or amount.
- Citation
- Shindel et al., 2010
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TribulusHuman study
Androgen measures with Tribulus extract in young men
Neychev and Mitev, 2005 · Randomized, placebo-controlled study over four weeks
Found no change in serum testosterone, androstenedione, or luteinizing hormone with either tested amount of Tribulus extract compared with placebo.
Limitation. An unfavorable finding. Small study in healthy young men over four weeks; it argues against, not for, a testosterone effect from this ingredient.
Read summary
- Design
- Randomized, placebo-controlled study over four weeks
- Participants
- 21 healthy men aged 20 to 36
- Measured outcome
- Serum testosterone, androstenedione, and luteinizing hormone
- Relevance to this formula
- The Tribulus in this blend has no disclosed specification or amount. This study does not support a testosterone-increase claim.
- Citation
- Neychev and Mitev, 2005
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Pumpkin Seed OilHuman study
Urinary symptom scores with pumpkin seed oil
Hong et al., 2009 · Randomized, double-blind, placebo-controlled study over 12 months
Reported lower urinary symptom scores in the pumpkin seed oil groups compared with placebo over the study period.
Limitation. Small study in men with a diagnosed prostate condition. It is not a prostate-treatment claim for this product and does not concern testosterone, energy, or desire.
Read summary
- Design
- Randomized, double-blind, placebo-controlled study over 12 months
- Participants
- 47 Korean men with symptomatic benign prostatic hyperplasia, average age 53
- Measured outcome
- International Prostate Symptom Score and quality-of-life score
- Relevance to this formula
- The pumpkin seed oil amount in this formula is not separately disclosed, and healthy men were not studied.
- Citation
- Hong et al., 2009
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Vitamin D3Human study
Testosterone measures with vitamin D in overweight men
Pilz et al., 2011 · Randomized, placebo-controlled trial over one year, within a weight-reduction program
Reported higher total testosterone at one year in the vitamin D group compared with baseline; the placebo group did not change.
Limitation. Participants were overweight, mostly low in vitamin D, and dieting. The result does not transfer to men with adequate vitamin D or normal testosterone.
Read summary
- Design
- Randomized, placebo-controlled trial over one year, within a weight-reduction program
- Participants
- 54 healthy overweight men, most with low vitamin D at baseline
- Measured outcome
- Circulating vitamin D and total testosterone
- Relevance to this formula
- The vitamin D3 amount in this formula is listed on the label; equivalence to the studied daily amount and duration is not established.
- Citation
- Pilz et al., 2011
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Vitamin D3Human study
Vitamin D and testosterone in healthy men
Lerchbaum et al., 2017 · Randomized, double-blind, placebo-controlled trial over 12 weeks
Found no effect of vitamin D3 on total testosterone in middle-aged healthy men with normal testosterone.
Limitation. An unfavorable finding. It shows that raising vitamin D did not raise testosterone in men whose testosterone was already normal.
Read summary
- Design
- Randomized, double-blind, placebo-controlled trial over 12 weeks
- Participants
- 98 healthy men with normal testosterone and low vitamin D
- Measured outcome
- Total testosterone measured by mass spectrometry
- Relevance to this formula
- Read alongside the Pilz study: vitamin D3 has not been shown to raise testosterone in men who are not deficient.
- Citation
- Lerchbaum et al., 2017
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Vitamin K2Animal research
Menaquinone-4 and testosterone production in rats
Ito et al., 2011 · Animal and cell-culture research over five weeks
Reported higher plasma and testicular testosterone in rats fed a menaquinone-4 supplemented diet compared with control animals.
Limitation. Animal research. It does not establish a human benefit, a human amount, or that the vitamin K2 in this formula does the same in men.
Read summary
- Design
- Animal and cell-culture research over five weeks
- Participants
- Male Wistar rats; testis-derived cell cultures
- Measured outcome
- Plasma and testicular testosterone
- Relevance to this formula
- The vitamin K2 form and amount in this formula are on the label; no human trial of that amount for testosterone is included here.
- Citation
- Ito et al., 2011
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Vitamin K1Ingredient overview
Vitamin K: health-professional fact sheet
NIH Office of Dietary Supplements · Ingredient overview, not a clinical trial
Summarizes what is known about phylloquinone (vitamin K1) and the menaquinones, their roles in clotting and bone, and the state of the research.
Limitation. Background reading on the vitamin, not a trial of this product. It does not link vitamin K1 to testosterone, energy, or desire.
Read summary
- Design
- Ingredient overview, not a clinical trial
- Measured outcome
- Summary of vitamin K forms, functions, intakes, and research
- Relevance to this formula
- Vitamin K1 is a labelled nutrient in this formula. Its presence does not establish any hormone-related result.
- Citation
- NIH Office of Dietary Supplements
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ZincHuman study
Zinc status and serum testosterone in men
Prasad et al., 1996 · Cross-sectional measures plus small dietary-restriction and supplementation studies
Reported lower testosterone after months of dietary zinc restriction in young men, and higher testosterone after three to six months of zinc supplementation in older men who were marginally zinc deficient.
Limitation. Very small groups, and the supplementation result was in men who were zinc deficient. It does not show that zinc raises testosterone in men with adequate zinc.
Read summary
- Design
- Cross-sectional measures plus small dietary-restriction and supplementation studies
- Participants
- 40 men aged 20 to 80; 4 young men on a zinc-restricted diet; 9 marginally zinc-deficient older men
- Measured outcome
- Cellular zinc and serum testosterone
- Relevance to this formula
- The zinc amount in this formula is on the label; the studied amount, duration, and deficient population are not matched here.
- Citation
- Prasad et al., 1996
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CistancheHuman study
Walking measures with a Cistanche tubulosa extract
Inada et al., 2021 · Randomized, double-blind, placebo-controlled study over 12 weeks
Reported improved step width and gait speed with the extract compared with placebo in the over-60 subgroup, with no change in muscle mass.
Limitation. Very small, mixed-sex study of a specific extract in older adults with a mobility condition. Walking measures are not strength, energy, or hormone outcomes.
Read summary
- Design
- Randomized, double-blind, placebo-controlled study over 12 weeks
- Participants
- 26 adults aged 40 to 80, mixed sex, with early or mild locomotive syndrome
- Measured outcome
- Two-step test and five-metre walking speed
- Relevance to this formula
- The Cistanche in this blend has no disclosed specification or amount, so equivalence to the studied extract is not established.
- Citation
- Inada et al., 2021
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