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Testosterone

The manly man hormone, testosterone is the most well known androgen that mediates androgenic processes such as muscle building, fat loss, some aspects of cognition and hair loss in some persons; important in puberty, it is sought after for its muscle building potential in men.

Our evidence-based analysis on testosterone features 176 unique references to scientific papers.

Kamal
Research analysis lead by Kamal Patel
All content reviewed by Examine.com Team. Published:
Last Updated:

Summary of Testosterone

Primary Information, Benefits, Effects, and Important Facts

If you are looking for an actual stack of supplements to take, we recommend you look at our increasing testosterone stack.

Things To Know & Note

Also Known As

test

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Frequently Asked Questions about Testosterone

Does ejaculation affect testosterone levels?
Ejaculation results in changes in prolactin (increase) and dopamine (temporary decrease), but does not result in changes in testosterone. Although prolactin and dopamine are both involved with testosterone, they do not appear to influence testosterone levels acutely.
Read full answer to "Does ejaculation affect testosterone levels?"
Does creatine cause hair loss?
It’s plausible, but unlikely. One RCT linked creatine supplementation to an increase in DHT — an androgen involved in hair loss — but this RCT has never been replicated.
Read full answer to "Does creatine cause hair loss?"
Do herbal aphrodisiacs work?
It depends on the product touted to be an aprhodisiac, but some of them do apparently increase sexual desire; it is a relatively underresearched topic though, and we don't know why they increase sexuality
Read full answer to "Do herbal aphrodisiacs work?"
Does ashwagandha increase testosterone?
There is a bit of evidence that shows Ashwagandha increases testosterone, but it is not convincing.
Read full answer to "Does ashwagandha increase testosterone?"
What is 'roid rage'?
Mostly a myth; testosterone (including injections) can increase impulsivity in some but this does not appear to be reliable (does not affect every person tested), impulsivity might lead to aggression but this is drawing at straws now with the connections
Read full answer to "What is 'roid rage'?"
Can creatine increase your testosterone levels?
There is no convincing evidence that creatine can increase your testosterone levels.
Read full answer to "Can creatine increase your testosterone levels?"
Is semen high in protein?
Yes. Semen is 50% protein by weight and contains a variety of nutrients to protect the sperm cells from damages.
Read full answer to "Is semen high in protein?"
How can you increase testosterone naturally?
When it comes to increasing your testosterone, quality sleep, physical activity, and weight management come first. A few supplements can help sustain healthy testosterone levels, but most supplements marketed as testosterone boosters don’t work, though some can make you believe they do by boosting your libido.
Read full answer to "How can you increase testosterone naturally?"
How important is sleep?
Sleep is incredibly important, and can be considered crucial alongside diet and exercise. Proper sleep habits help sustain many biological processes, and bad sleep can cause these processes to be suboptimal or even malfunction.
Read full answer to "How important is sleep?"
Four Testosterone Boosters and Sketchy Research
Read full answer to "Four Testosterone Boosters and Sketchy Research"

Human Effect Matrix

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what supplements affect testosterone
Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
Notes
grade-a Dehydroepiandrosterone Notable High See all 18 studies
There appears to be an increase in testosterone following DHEA supplementation, but the vast majority of literature is in menopausal women (where testosterone contributes to libido). There is variability in the results, and DHEA is unreliable in increasing testosterone, but this unreliability extends to all demographics and subjects (with limited evidence of DHEA increasing testosterone in all studies including youthful athletes, which are less studied).
grade-b Alcohol
Minor 		- See all 9 studies
There appears to be a time-dependent influence on testosterone, with acute doses of alcohol increasing testosterone secondary to creating energy influx in the liver (small enough of an increase to be 'somewhat' effective but may contribute to libido) whereas abuse is known to reduce testosterone levels more notably. The acute increase in testosterone is thought to be related to spikes in libido
grade-b Caffeine Minor High See all 4 studies
A very small (usually 12%) increase is noted in trained athletes consuming caffeine above 250mg prior to exercise, this may be dependent on exercise as studies without exercise fail to find alterations in testosterone. This increase in unlikely to lead to significant testosterone-like effects
grade-b Creatine  
grade-b Zinc  
grade-b Fenugreek  
grade-b HMB  
grade-b Maca  
grade-b Red Clover Extract  
grade-b Tribulus terrestris  
grade-b Velvet Antler  
grade-c Ashwagandha  
grade-c Coenzyme Q10  
grade-c Coleus forskohlii  
grade-c D-Aspartic Acid  
grade-c Licorice  
grade-c Mucuna pruriens  
grade-c Panax ginseng  
grade-c Royal Jelly  
grade-c Shilajit  
grade-c Vitamin D  
grade-c 7-Keto DHEA  
grade-c Alanylglutamine  
grade-c Arachidonic acid  
grade-c Arginine  
grade-c Astaxanthin  
grade-c Beta-Alanine  
grade-c Chromium  
grade-c Chrysin  
grade-c Colostrum  
grade-c Ecdysteroids  
grade-c Eurycoma Longifolia Jack  
grade-c Fish Oil  
grade-c Gamma Oryzanol  
grade-c Ganoderma lucidum  
grade-c Garcinia cambogia  
grade-c Glutamine  
grade-c Green Tea Catechins  
grade-c L-Carnitine  
grade-c Magnesium  
grade-c Nicotine  
grade-c Phosphatidylserine  
grade-c Saffron  
grade-c Saw Palmetto  
grade-c Stinging Nettle  
grade-d Boron  
grade-d Ginger  
grade-d Calcium  
grade-d Grape Seed Extract  
grade-d Punicalagins  
grade-d Rubus coreanus  
grade-d Yohimbine  

All comparative evidence is now gathered in our ​A-to-Z Supplement Reference.

The evidence for each separate supplement is still freely available ​here.

References

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