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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 Patel
Research analysis led by Kamal Patel.
All content reviewed by the Examine.com Team. Published: Nov 14, 2012
Last Updated:

Summary of Testosterone

Primary Information, Benefits, Effects, and Important Facts

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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
Ashwagandha
Minor Very High See all 6 studies
Testosterone may be increased in infertile men (who have a reduction in testosterone) and men undergoing strength training, but there is currently no evidence to suggest an inherent testosterone boosting effect in otherwise normal men.

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

The evidence for each separate supplement is still freely available ​here.
grade-b
Caffeine
 
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
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
Curcumin
 
grade-d
Grape Seed Extract
 
grade-d
Punicalagins
 
grade-d
Rubus coreanus
 
grade-d
Yohimbine
 

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