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Raise Your Testosterone Naturally

Low testosterone

Also called Raising it naturally, Low T, Boosting testosterone, Natural testosterone

3 min plan52 min with every studyUpdated Sep 27, 2026

Who it's forA man who thinks his testosterone is low, or wants it higher, and wants to try without a prescription first.

This week

  1. Book two fasting morning draws, a few days apart
  2. Add SHBG, LH, FSH, HbA1c and ferritin to the first
  3. Write down everything you take and have taken
  4. Trying for a child? Tell the doctor first
  5. After the second draw: sleep, drink, the belly

The plan

The pituitaryLHThe signalThe testicle's outputtestosteroneThe free fraction
Figure 1. The loop the plan works on. The pituitary sends LH, LH tells the testicle to make testosterone, and most of what reaches the blood is held by a carrier protein. Fix what turns the signal down and the testicle does the rest.

19 moves, in order, after 3 checks. Tap any row to see how.

Check first

The morning blood drawTwo fasting morning draws before any changeCheck

The morning blood draw

For: Everyone

A blood test tells you where you actually start. Without it you are guessing.

How to check

  1. Book a fasting blood test between 7 and 10 in the morning.
  2. Ask for total testosterone and SHBG, so free testosterone can be calculated.
  3. Repeat it on a second morning a few days later, before you change anything.
  4. Not while you are ill. Wait until you are well.
What it is
Two blood tests
When
Fasting, 7 to 10am
How often
Week 0, again at week 12

Reading the number

Measure first, twice

Low means under 264 to 300 ng/dL on two fasting morning tests. Free testosterone is worked out from the total and the binding protein.

¹ The Journal of clinical endocrinology and metabolism, 2018. The study is under The science, below.

The science
In detail
Book a fasting blood draw between 7 and 10 in the morning: total testosterone and SHBG, the binding protein, so free testosterone can be calculated. Repeat it on a second morning a few days later, before you change anything. Not while you are ill.
Found
Two morning draws. The endocrine guideline: fasting morning total testosterone on a reliable assay first, confirmed on a second morning. Free testosterone by equilibrium dialysis or an accurate formula when the total sits near the line or the binding protein is off. A review: low is under 264 to 300 ng/dL on two fasting samples taken between 7 and 10 am. Severe illness is one of the reversible causes.
Why
Testosterone peaks in the morning and swings through the day, so an afternoon number reads low. A severe illness pulls it down, so a draw taken while ill misreads you. Two morning draws separate a real low from a bad day.
How it is done
Total testosterone and SHBG; Fasting, 7 to 10am; Week 0, twice; then week 12

The studies

We recommend measuring fasting morning total T concentrations using an accurate and reliable assay as the initial diagnostic test.

PMID 29562364 · Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline. · The Journal of clinical endocrinology and metabolism, 2018

Hypogonadism is confirmed if an individual's serum testosterone concentration is less than 264 to 300 ng/dL in at least 2 fasting samples collected between 7 and 10 am

PMID 42207626 · Adult Male Hypogonadism: A Review. · JAMA, 2026

The sentence around it

Hypogonadism is confirmed if an individual's serum testosterone concentration is less than 264 to 300 ng/dL in at least 2 fasting samples collected between 7 and 10 am and measured with an accurate and external quality-controlled assay.…

The cause tests, on the same drawLH, FSH, HbA1c, ferritin and zinc; prolactin if LH is lowCheck

The cause tests, on the same draw

For: Everyone

The same blood draw can show why the number is low. That changes what fixes it.

How to check

  1. Add LH and FSH to the first blood test.
  2. Add HbA1c for blood sugar, ferritin for iron and a zinc level.
  3. If LH comes back low or low-normal, ask for prolactin.
What it is
A few extra markers
When
On the first draw
How often
Once

Reading the number

Find the cause

LH and FSH show whether the testicles or the brain's signal is the cause. High prolactin and iron overload are classic causes a doctor treats directly.

¹ JAMA, 2026. The study is under The science, below.

The science
In detail
Add LH and FSH to the first draw, with HbA1c for blood sugar, ferritin for iron and a zinc level. If LH comes back low or low-normal, ask for prolactin. These point at the cause.
Found
LH, FSH, HbA1c, ferritin, zinc. A review: every man found low should have LH and FSH measured, to tell a testicle problem from a signal problem. Low testosterone with low or inappropriately normal LH is the signal side. Diabetes lowers the binding protein, so free testosterone has to be calculated. The classic causes include high prolactin and iron overload.
Why
A low number is a finding, not a diagnosis. LH says which end failed. High prolactin, blood sugar and iron overload are named causes, and each is treated at the source.
How it is done
LH, FSH, HbA1c, ferritin; prolactin if LH is low; On the first draw; Week 0

The studies

Patients diagnosed with hypogonadism should have serum FSH and LH concentrations measured to distinguish primary from secondary hypogonadism.

PMID 42207626 · Adult Male Hypogonadism: A Review. · JAMA, 2026

The classic causes of male androgen deficiency-hyperprolactinemia, pituitary macroadenoma, endogenous Cushing syndrome, and iron overload syndrome-are rare

PMID 35216709 · Epidemiology of Male Hypogonadism. · Endocrinology and metabolism clinics of North America, 2022

The sentence around it

The classic causes of male androgen deficiency-hyperprolactinemia, pituitary macroadenoma, endogenous Cushing syndrome, and iron overload syndrome-are rare (prevalence < 10,000 men).…

Two low draws: see a doctorLow twice with symptoms, or a warning sign: a doctorCheck

Two low draws: see a doctor

For: Two low results

If both tests come back low and you feel it, a doctor finds out why. Some signs mean you go now, without waiting.

How to check

  1. Take both test results to a doctor.
  2. Describe your symptoms: energy, sex drive, mood, sleep, morning erections.
  3. Go now, without waiting, for a very low result, headaches, vision changes, milky nipple discharge, breast growth, small testes or trouble conceiving.
  4. Trying for a child? Ask about the routes that protect sperm production.
  5. Ask what is causing it.
What it is
One appointment
When
After two low tests, or a warning sign
How often
Until you know why

Standard practice

A pituitary scan is standard when testosterone is under 150 ng/dL with a low brain signal, prolactin stays high, or headaches or vision changes appear.

Reading the number

Find the cause, then treat

The Endocrine Society guideline says low testosterone is diagnosed only with symptoms and two clearly low tests. The cause gets checked first. With extra weight, weight loss usually comes first.

¹ The Journal of clinical endocrinology and metabolism, 2018. The study is under The science, below.

Watch out

Headaches, vision changes or milky nipple discharge with a low result: see a doctor now.

The science
In detail
If both morning draws come back low and you have the symptoms, the next step is a doctor, not a stronger supplement. Take both numbers with you. Some signs skip the wait: a very low number, headaches or a change in vision, milky discharge from a nipple, small testes, breast growth, or trouble conceiving.
Found
Symptoms plus two low draws. The endocrine guideline: diagnose low testosterone only with symptoms and signs of deficiency and a testosterone that is unequivocally and consistently low, then look for the cause. High prolactin is among the most common causes of a low signal, and it often shows as headaches and vision loss from the pituitary. The endocrinologists' July 2026 statement: with a BMI over 27 and no other cause, weight loss is typically first. Since February 2025 the US testosterone label carries no heart-risk boxed warning and adds a blood pressure warning. For a man trying for a child, prescription routes such as hCG and clomiphene work through his own hormones and are used to protect sperm production.
Why
A low number with symptoms can be a pituitary problem, a medication, sleep apnea or weight. Tiredness and low drive are also signs of low mood and sleep apnea, so the doctor checks those too. Finding the cause comes before treating the number.
How it is done
Both draws, and your symptoms; After the second low draw; When it happens

The studies

We recommend making a diagnosis of hypogonadism only in men with symptoms and signs consistent with testosterone (T) deficiency and unequivocally and consistently low serum T concentrations.

PMID 29562364 · Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline. · The Journal of clinical endocrinology and metabolism, 2018

The sentence around it

…Conclusions We recommend making a diagnosis of hypogonadism only in men with symptoms and signs consistent with testosterone (T) deficiency and unequivocally and consistently low serum T concentrations.

preventive strategies, such as transitioning to short-acting testosterone formulations or incorporating low-dose hCG to preserve fertility during ET therapy

PMID 39820213 · Clinician's guide to the management of azoospermia induced by exogenous testosterone or anabolic-androgenic steroids. · Asian journal of andrology, 2025

The sentence around it

…Additionally, the manuscript discusses preventive strategies, such as transitioning to short-acting testosterone formulations or incorporating low-dose hCG to preserve fertility during ET therapy.…

Free habits

1Check what you takeList past steroids, SARMs, opioids and steroid tablets firstModerate evidence

Check what you take

For: Everyone

Some drugs switch off the signal that makes testosterone. If one of them is the cause, nothing else on this page will move the number.

What to do

  1. Write down every medicine and supplement you take, and anything you took in the past.
  2. Include any past steroid or SARM use, opioid painkillers and steroid tablets.
  3. Bring the list to the doctor with the blood test.
How much
One written list
When
Before the first test
How long
Once

What happened in the studies

Still low 2.5 years later

Men who had used steroids were still lower on testosterone about 2.5 years after stopping. Long-term opioid painkillers lower it in 20% to 80% of users, and steroid tablets can lower it too.

¹ PloS one, 2016. The study is under The science, below.

Watch out

Never stop a prescribed painkiller or steroid tablet suddenly. Taper it with the doctor who prescribed it.

The science
In detail
Before any supplement: list what you take and what you have taken. Past steroid or SARM use, long-term opioid painkillers and steroid tablets such as prednisolone all switch the signal off. Tell the doctor, because it changes what the number means.
Found
Former steroid users were still lower on total and free testosterone than controls an average of 2.5 years after stopping, with more symptoms of low testosterone. A review names opioids, corticosteroids and drugs that raise prolactin among the common reversible causes. Long-term opioid painkillers lower it in between 20% and 80% of users, depending on the drug and how long.
Why
Each suppresses the signal from the brain that tells the testicles to make testosterone. Nothing else on this page can override that while it is switched off.
Watch
Never stop a prescribed opioid or steroid tablet abruptly; taper it with the prescriber.

The studies

Former AAS abusers exhibited significantly lower plasma testosterone levels and higher frequencies of symptoms suggestive of hypogonadism than healthy control participants years after AAS cessation.

PMID 27532478 · Former Abusers of Anabolic Androgenic Steroids Exhibit Decreased Testosterone Levels and Hypogonadal Symptoms Years after Cessation: A Case-Control Study. · PloS one, 2016

The sentence around it

…Conclusions Former AAS abusers exhibited significantly lower plasma testosterone levels and higher frequencies of symptoms suggestive of hypogonadism than healthy control participants years after AAS cessation.

The most common potentially reversible causes of secondary hypogonadism are obesity, severe illness, and medication use (opioids, corticosteroids, checkpoint inhibitors, and medications that cause hyperprolactinemia).

PMID 42207626 · Adult Male Hypogonadism: A Review. · JAMA, 2026

2Trying for a child: tell the doctorTrying for a child: tell the doctor firstModerate evidence

Trying for a child: tell the doctor

For: Trying for a child

Hormones from outside switch sperm production off. Some supplements have been found secretly spiked with them.

What to do

  1. Tell the doctor you are trying for a child.
  2. Take nothing for testosterone without asking first.
  3. Bring the list of what you take.
How much
One conversation
When
Before anything else
How long
While trying

What happened in the studies

Tell the doctor first

In 50 studies, 875 of 3,132 supplements held hidden ingredients, most often steroids or a diet drug. Steroids shut sperm production down.

¹ Asian journal of andrology, 2025. The study is under The science, below.

The science
In detail
If you are trying for a child, tell the doctor before you take anything for testosterone. Testosterone and steroids from outside switch sperm production off, and some supplements have been found spiked with steroids.
Found
875 of 3,132 held hidden drugs. A review of 50 studies: 875 of 3,132 supplements tested held undeclared substances, most often sibutramine and anabolic steroids. A clinical review: outside testosterone and steroids suppress the brain's signal, lowering testosterone inside the testicle and impairing sperm production.
Why
Sperm are made on the testosterone inside the testicle, which runs on the brain's signal. Hormone from outside shuts that signal down, and the testicle's own supply falls with it.

The studies

These agents suppress the hypothalamic-pituitary-gonadal (HPG) axis, leading to reduced intratesticular testosterone levels and impaired spermatogenesis.

PMID 39820213 · Clinician's guide to the management of azoospermia induced by exogenous testosterone or anabolic-androgenic steroids. · Asian journal of andrology, 2025

Most frequently found undeclared substances are sibutramine and anabolic-androgenic steroids.

PMID 35496041 · Dietary Supplements as Source of Unintentional Doping. · BioMed research international, 2022

3SleepSeven to eight hours, at the same timesStrong evidence

Sleep

For: Everyone

Your body makes testosterone while you sleep. A whole lost night pulls the number down.

What to do

  1. Sleep 7 to 8 hours.
  2. Keep the same times, seven days a week.
How much
7 to 8 hours
When
Same times daily
How long
For good

What happened in the studies

A lost night drops testosterone

In 18 studies, one whole night without sleep pulled testosterone down clearly.

¹ Sleep medicine, 2021. The study is under The science, below.

Watch out

Snoring or stopping breathing at night? Get tested for sleep apnea first.

The science
In detail
Seven to eight hours asleep, at the same times, seven days a week. Testosterone is made through the night and peaks in the morning, which is when the draw finds it.
Found
A medium effect from a lost night. Eighteen studies, 252 people: a whole night without sleep pulled testosterone down by two thirds of a standard deviation. Sleep duration is what holds the morning number up.
Why
Testosterone rises through the night with sleep and peaks after waking. Cut the night short and the rise never finishes. Regular timing keeps the morning peak where the draw finds it.
Watch
Snoring, breathing that stops, sleep that does not refresh: get tested for apnea before you blame the hormone.

The study

total sleep deprivation reduced the male testosterone levels (SMD = -0.64; 95% CI: -0.87, -0.42

PMID 34801825 · Effect of partial and total sleep deprivation on serum testosterone in healthy males: a systematic review and meta-analysis. · Sleep medicine, 2021

The sentence around it

total sleep deprivation reduced the male testosterone levels (SMD = -0.64; 95% CI: -0.87, -0.42; P < 0.001).…

Sleep duration plays a pivotal role in maintaining male serum testosterone levels.

The deep dive on this

4Body fat downGet the body fat down; the Lose fat page is the methodStrong evidence

Body fat down

For: Carrying extra fat

Belly fat turns testosterone into estrogen. Losing it raises your testosterone.

What to do

  1. Lose fat slowly and steadily.
  2. Keep the protein up and keep lifting, so what you lose is fat and not muscle.
How much
Slow and steady
When
Steadily
How long
12 weeks, then test

What happened in the studies

Testosterone rises

In 24 studies, losing weight, by diet or surgery, raised both total and free testosterone. Carrying extra weight, losing at least 5% typically raises it.

¹ European journal of endocrinology, 2013. The study is under The science, below.

The science
In detail
Get the belly off. Fat tissue carries the enzyme that turns testosterone into estrogen. Lose it slowly, with the fat kept on the plate.
Found
24 studies. Twenty-four studies: weight lost by diet or by surgery came with a rise in both bound and free testosterone. A review: with obesity, losing at least 5% of body weight typically raises total testosterone, and weight loss is the first-line treatment.
Why
Fat tissue carries aromatase, the enzyme that converts testosterone to estrogen, and the estrogen turns the pituitary's signal down. Less fat, less conversion, more signal.

The studies

weight loss is associated with an increase in both bound and unbound testosterone levels

PMID 23482592 · Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis. · European journal of endocrinology, 2013

The sentence around it

…Conclusions These data show that weight loss is associated with an increase in both bound and unbound testosterone levels.…

In men with obesity, weight loss of at least 5% typically increases serum total testosterone concentration significantly

PMID 42207626 · Adult Male Hypogonadism: A Review. · JAMA, 2026

The sentence around it

In men with obesity, weight loss of at least 5% typically increases serum total testosterone concentration significantly, and weight loss is associated with improved physical function, libido, and erectile function.…

5Keep the fat in the dietLose the belly without going low-fatModerate evidence

Keep the fat in the diet

For: Everyone losing weight

Cutting fat out of your diet can lower testosterone. Lose weight by eating less, not by going low-fat.

What to do

  1. Keep eggs, meat, fish, olive oil, nuts and dairy in the diet.
  2. Cut the total amount you eat, not the fat.
  3. Let the belly come down slowly.
How much
Normal fat intake
When
Every meal
How long
For good

What happened in the studies

Low-fat diets lowered it

Across six studies, low-fat diets gave lower total and free testosterone than diets that kept the fat in.

¹ The Journal of steroid biochemistry and molecular biology, 2021. The study is under The science, below.

The science
In detail
Lose the belly without cutting fat out of the plate. The trials that went low-fat saw testosterone fall.
Found
-0.38 on low-fat diets. Six studies, 206 people, low-fat against high-fat diets: total testosterone down (standardized difference -0.38), and free testosterone down (-0.37).
Why
Testosterone is built from cholesterol, and the fat in a meal feeds that line. Cut it hard and the testicles have less to work with.

The study

total testosterone [-0.38 (95 % CI -0.75 to -0.01) P = 0.04]; free testosterone [-0.37 (95 % CI -0.63 to -0.11) P = 0.005]

PMID 33741447 · Low-fat diets and testosterone in men: Systematic review and meta-analysis of intervention studies. · The Journal of steroid biochemistry and molecular biology, 2021

The sentence around it

…Standardised mean differences with 95 % confidence intervals (CI) for outcomes were: total testosterone [-0.38 (95 % CI -0.75 to -0.01) P = 0.04]; free testosterone [-0.37 (95 % CI -0.63 to -0.11) P = 0.005]; urinary testosterone [-0.38 (CI 95 % -0.66 to -0.09) P = 0.009]; and dihydrotestosterone [-0.3 (CI 95 % -0.56 to -0.03) P = 0.03].…

Low-fat diets appear to decrease testosterone levels in men

The sentence around it

…Conclusions Low-fat diets appear to decrease testosterone levels in men

6Aerobic training, if you carry extra weightModerate evidence

Aerobic training, if you carry extra weight

For: Extra weight, high blood sugar

If you carry extra weight, regular cardio raises testosterone. Very heavy endurance training for years can lower it.

What to do

  1. Do cardio that gets you breathing hard, most weeks.
  2. Build up slowly.
  3. Retest at 12 weeks.
How much
Regular cardio
When
Most weeks
How long
12 weeks, then test

What happened in the studies

A moderate rise

Across seven studies, aerobic training moderately raised testosterone where weight or blood sugar ran high.

¹ Sports medicine - open, 2024. The study is under The science, below.

Watch out

Years of very heavy endurance training can lower testosterone instead.

The science
In detail
If you carry extra weight or your blood sugar runs high: regular aerobic work, the kind that gets you breathing hard, most weeks. Years of very heavy endurance training go the other way.
Found
g 0.565. Seven studies, 103 people, where weight or blood sugar ran high: aerobic training moderately raised testosterone (g = 0.565). A short review: years of endurance sports training go with persistently lower free and total testosterone.
Why
Aerobic work burns the fat that turns testosterone into estrogen, and it improves how the body handles sugar. At the extreme end, the chronic training load itself suppresses the signal.
Watch
Years of heavy endurance training can lower testosterone.

The studies

Aerobic exercise moderately increased testosterone concentrations in men (g = 0.565, 95% CI = 0.307 to 0.822

PMID 39467940 · The Effects of Aerobic Exercise Training on Testosterone Concentration in Individuals Who are Obese or Have Type 2 Diabetes: A Systematic Review and Meta-Analysis. · Sports medicine - open, 2024

Men chronically exposed to training for endurance sports exhibit persistently reduced basal free and total testosterone concentrations without concurrent luteinizing hormone elevations.

PMID 32724267 · Reproductive Dysfunction from Exercise Training: The "Exercise-Hypogonadal Male Condition". · Archivos de medicina del deporte, 2019

7Drinking less without quittingUnder four US standard drinks (seven UK units) a week; none most nightsModerate evidence

Drinking less without quitting

For: Everyone

Heavy drinking lowers testosterone and raises estrogen.

What to do

  1. Keep it under 4 US standard drinks (7 UK units) a week.
  2. None on most nights.
How much
Under 4 US standard drinks (7 UK units) a week
When
Every week
How long
For good

What happened in the studies

Drinking lowers it

In 40 studies with 23,258 people, drinking lowered testosterone. Over 4 US standard drinks (7 UK units) a week, estrogen rose too.

¹ Heliyon, 2023. The study is under The science, below.

Watch out

If you drink every day and shake without it, stopping suddenly is a medical danger. See a doctor first.

The science
In detail
Keep it under four US standard drinks (seven UK units) a week, and none on most nights. Drinking lowered testosterone across the studies, and over four US standard drinks (seven UK units) a week estradiol rose.
Found
Drinking: T down; over 4 US standard drinks (7 UK units): estradiol up. Forty studies, 23,258 people: drinking lowered testosterone overall. Over four US standard drinks (seven UK units) a week, the sex hormones worsened and estradiol rose; under four, the semen numbers held.
Why
Alcohol hits the testicle directly and the pituitary above it, which sends less LH. Heavy drinking also pushes estrogen up.
Watch
Physical dependence, where cutting abruptly is a medical event and not a plan.

The study

the group of heavy alcoholics (more than 7 units/week) harmed the semen index and sex hormones, especially by increasing estradiol

PMID 37159717 · Investigating the association between alcohol intake and male reproductive function: A current meta-analysis. · Heliyon, 2023

The sentence around it

…Meanwhile, the group of heavy alcoholics (more than 7 units/week) harmed the semen index and sex hormones, especially by increasing estradiol.…

the results showed a decrease in general testosterone levels (SMD = -1.60; 95% CI -2.05, -1.15)

The sentence around it

…Finally, the results showed a decrease in general testosterone levels (SMD = -1.60; 95% CI -2.05, -1.15)

The deep dive on this

Over the counter

8Tongkat Ali200 mg a day of the standardized extractModerate evidence

Tongkat Ali

For: Testosterone

A root extract that raises testosterone.

What to do

  1. Take 200 mg of standardized extract a day.
  2. Only a batch with a third-party test for heavy metals.
  3. Take nothing else new, and judge it on a blood test after 12 weeks.
How much
200 mg
When
Once a day
How long
12 weeks alone, then test

What happened in the studies

Big rise in testosterone

In 5 trials, testosterone rose a lot. In one, where most started low, 91% had a normal level after a month, up from 36%.

¹ Medicina (Kaunas, Lithuania), 2022. The study is under The science, below.

Watch out

Often faked or spiked with other drugs. In two market surveys of tongkat ali products, a quarter to a third carried mercury above the legal limit. Choose a product with a third-party test for heavy metals. It is not authorized as a food in the EU, where a safety review raised a DNA-damage concern.

The science
In detail
200 mg a day of the standardized water extract. Choose a batch with a lab certificate, because adulteration is the risk with this plant.
Found
A large effect on total T. Five trials pooled: total testosterone up by 1.35 standard deviations. Two trials, 139 people: the erection score rose 2.15 points where it started low. Seventy-six people, most of whom started low, on 200 mg for a month: 35.5% had a normal testosterone before, 90.8% after.
Why
The pooled trials measured total testosterone going up, where it started normal and where it started low. It raises what the testicle makes; judge it on your own draw.
Watch
Product contamination and adulteration: this is the plant most often found spiked or substituted. In two market surveys of tongkat ali products, a quarter to a third carried mercury above the legal limit. Choose a product with a third-party test for heavy metals. In the EU it is not authorized as a food; the food safety panel could not establish its safety and flagged possible DNA damage.
The doses the studies used200 mg one month: nine in ten ended with a normal testosterone
200 mg400 mg

were given 200 mg of a standardised water-soluble extract of Tongkat ali for 1 month PMID 21671978

The studies

The random model effect revealed a significant increase (SMD = 1.352, 95% CI 0.565 to 2.138, p = 0.001) in the total testosterone levels in men receiving E. longifolia supplementation

PMID 36013514 · Eurycoma longifolia (Jack) Improves Serum Total Testosterone in Men: A Systematic Review and Meta-Analysis of Clinical Trials. · Medicina (Kaunas, Lithuania), 2022

The sentence around it

The random model effect revealed a significant increase (SMD = 1.352, 95% CI 0.565 to 2.138, p = 0.001) in the total testosterone levels in men receiving E. longifolia supplementation, which was confirmed in the hypogonadism subgroup.…

2 studies involving a total of 139 participants were analyzed

PMID 26365449 · Efficacy of Tongkat Ali (Eurycoma longifolia) on erectile function improvement: systematic review and meta-analysis of randomized controlled trials. · Complementary therapies in medicine, 2015

The sentence around it

…Results Of the 342 articles identified, 2 studies involving a total of 139 participants were analyzed.…

The deep dive on this

9ZincAbout 30 mg a day, only if your level is lowModerate evidence

Zinc

For: Low zinc

If your zinc is low, putting it back restores testosterone.

What to do

  1. Test your zinc first.
  2. If it is low, ask the doctor about the trial's 30 mg a day with food.
  3. Stop after 3 to 6 months.
How much
About 30 mg
When
With food
How long
3 to 6 months

Standard practice

UK advice is no more than 25 mg of zinc supplements a day unless a doctor advises it. The trial's 30 mg is above that, so take it with the doctor who found the low level.

What happened in the studies

Doubled if you were low

In a small study, 6 months of zinc took testosterone from 239 to 461 ng/dL (8.3 to 16.0 nmol/L) where zinc started low.

¹ Journal of trace elements in medicine and biology, 2023. The study is under The science, below.

Watch out

Long daily use drains copper and can cause anemia. With ciprofloxacin, take the antibiotic 2 hours before or 6 hours after the zinc. With doxycycline, keep the two as far apart in the day as you can.

The science
In detail
Only if your zinc is low. The trial dose was 459 µmol a day, about 30 mg, as zinc gluconate for three to six months. Not daily forever: the copper goes.
Found
8.3 to 16.0 nmol/L, if deficient. Thirty-eight studies reviewed: a zinc deficiency lowers testosterone and putting the zinc back restores it. In a small study without a comparison group, nine people who were marginally short went from 8.3 to 16.0 nmol/L after six months of zinc.
Why
Zinc sits in the enzymes that make testosterone and in the receptor that reads it. Twenty weeks of a zinc-poor diet cut testosterone by three quarters in the same study. The mineral is a floor, not a lever.
Watch
Copper deficiency and anemia with long daily zinc. Zinc blocks some antibiotics. Take a quinolone such as ciprofloxacin at least 2 hours before or 6 hours after it. Keep a tetracycline such as doxycycline as far from it as you can.
The doses the studies usedAbout 30 mg the trial's 459 micromoles a day, as zinc gluconate, three to six months, from a marginal deficiency
About 30 mg

supplementation with 459 mumol/ d oral zinc administered as zinc gluconate PMID 8875519

The studies

zinc deficiency reduces testosterone levels and zinc supplementation improves testosterone levels

PMID 36577241 · Correlation between serum zinc and testosterone: A systematic review. · Journal of trace elements in medicine and biology, 2023

The sentence around it

…We concluded that zinc deficiency reduces testosterone levels and zinc supplementation improves testosterone levels.…

resulted in an increase in serum testosterone from 8.3 +/- 6.3 to 16.0 +/- 4.4 nmol/L (p = 0.02)

PMID 8875519 · Zinc status and serum testosterone levels of healthy adults. · Nutrition (Burbank, Los Angeles County, Calif.), 1996

The sentence around it

resulted in an increase in serum testosterone from 8.3 +/- 6.3 to 16.0 +/- 4.4 nmol/L (p = 0.02).…

The deep dive on this

10Shilajit250 mg twice a day for ninety daysModerate evidence

Shilajit

For: Testosterone

A mineral resin that raised testosterone in a 90-day trial.

What to do

  1. Take 250 mg of purified shilajit twice a day.
  2. Only a batch tested for heavy metals.
  3. Give it 90 days.
How much
250 mg, twice
When
Morning and evening
How long
90 days

What happened in the studies

Up in 90 days

After 90 days at 250 mg twice a day, total and free testosterone rose against a dummy pill.

¹ Andrologia, 2016. The study is under The science, below.

Watch out

Untested product can carry lead, arsenic and mercury.

The science
In detail
250 mg of purified shilajit twice a day for ninety days. Only a batch with a heavy-metal certificate: raw shilajit is a rock, and it carries lead.
Found
Total and free T up at 90 days. Ninety days at 250 mg twice a day: total and free testosterone and DHEA-S all rose against placebo, and the pituitary signals held.
Why
Fulvic acid ferries minerals into cells. The pigment part may recycle CoQ10 in the mitochondria that make the hormone. How it works is still a theory. The trial is the proof.
Watch
Heavy metal contamination: lead, arsenic and mercury in untested product.
The doses the studies used250 mg, twice a day the ninety-day trial: total and free testosterone up
250 mg, twice a day

at a dose of 250 mg twice a day PMID 26395129

The study

Treatment with Shilajit for consecutive 90 days revealed that it has significantly (P < 0.05) increased total testosterone, free testosterone and dehydroepiandrosterone (DHEAS) compared with placebo.

PMID 26395129 · Clinical evaluation of purified Shilajit on testosterone levels in healthy volunteers. · Andrologia, 2016

Gonadotropic hormones (LH and FSH) levels were well maintained.

The deep dive on this

11AshwagandhaA standardized extract daily, for eight weeksModerate evidence

Ashwagandha

For: Testosterone, stress

An herb best known for stress and sleep. Across the trials pooled, it also raised testosterone.

What to do

  1. Take an extract giving 21 mg of withanolide glycosides once a day.
  2. Give it eight weeks.
  3. Judge it on your next blood test.
How much
21 mg withanolide glycosides
When
Once a day
How long
8 weeks, then test

What happened in the studies

About 57 ng/dL more than placebo

Across the pooled trials, testosterone rose about 57 ng/dL more than on a dummy pill. Check it on your own blood test.

¹ Planta medica, 2026. The study is under The science, below.

Watch out

Stomach upset and drowsiness. Stop if your eyes or skin turn yellow. Ask first if you have a thyroid or autoimmune problem, have surgery coming, or take medicine for diabetes, blood pressure, seizures, the thyroid or the immune system, or a sedative. Not with hormone-sensitive prostate cancer. It cannot legally be sold in Denmark.

The science
In detail
The trial's product: an extract giving 21 mg of withanolide glycosides a day, for eight weeks, then judge it on your own blood draw.
Found
57.43 ng/dL more than placebo. Pooled trials against a placebo: men's testosterone rose by 57.43 ng/dL more than on placebo, and cortisol fell. In one eight-week trial, testosterone rose 14.7% more than on placebo, and DHEA-S 18% more.
Why
It turns down the stress-hormone system. In the pooled trials, cortisol, the main stress hormone, fell against placebo. Testosterone rose alongside it.
Watch
Drowsiness, stomach upset, diarrhea and vomiting in some. Rare liver injury has been reported: stop at yellow eyes or skin, or dark urine. It is not recommended with an autoimmune or thyroid disorder, or before surgery. Avoid it with hormone-sensitive prostate cancer, because it may raise testosterone. It may interact with medicines for diabetes, blood pressure, the immune system, seizures and the thyroid, and with sedatives. It cannot legally be sold as a food in Denmark.
The doses the studies used21 mg glycosides the trial's daily dose, for eight weeks
21 mg glycosides

delivering 21 mg of withanolide glycosides a day PMID 30854916

The studies

Ashwagandha supplementation appears to modulate key hormonal pathways, particularly cortisol and sex hormones.

PMID 41740946 · Hormonal Modulation with Withania somnifera: Systematic Review and Meta-Analysis of Randomized-controlled Trials. · Planta medica, 2026

Ashwagandha intake was associated with an 18% greater increase in DHEA-S ( p = .005) and 14.7% greater increase in testosterone ( p = .010) compared to the placebo.

PMID 30854916 · A Randomized, Double-Blind, Placebo-Controlled, Crossover Study Examining the Hormonal and Vitality Effects of Ashwagandha ( Withania somnifera) in Aging, Overweight Males. · American journal of men's health, 2019

The deep dive on this

12Fenugreek500 mg a day of a seed extract; judge on the next drawModerate evidence

Fenugreek

For: Testosterone

A seed extract. Four small trials pooled found it raised total testosterone.

What to do

  1. Take 500 mg of a fenugreek seed extract once a day.
  2. Judge it on a blood test after 12 weeks.
How much
500 mg
When
Once a day
How long
12 weeks, then test

What happened in the studies

A rise across 4 trials

Four trials pooled found fenugreek raised total testosterone. In a 12-week study at 500 mg a day, free testosterone rose in most who took it.

¹ Phytotherapy research, 2020. The study is under The science, below.

Watch out

Stomach upset and a maple-syrup body smell. It can lower blood sugar. Ask first if you take warfarin or diabetes medicine. Skip it if you are allergic to peanuts or chickpeas.

The science
In detail
A seed extract, 500 mg a day, the dose a 12-week study ran. The pooled trials found a rise in total testosterone; judge it on your own draw.
Found
4 trials pooled. Four trials pooled: fenugreek extract had a clear effect on total testosterone against the comparison group. In a 12-week study of 50 people on 500 mg a day, free testosterone rose by up to 46% in 90% of them.
Why
Its seed glycosides act on the testosterone line in ways the trials have not pinned down. The effect in the pooled trials was on total testosterone.
Watch
Gut effects and a maple-syrup body odor. It can lower blood sugar. It can interact with warfarin to cause bleeding, and it can cross-react in people allergic to peanuts or chickpeas.
The doses the studies used500 mg a day for twelve weeks, an open study without a placebo group
500 mg

to determine the efficacy of FS (500 mg/day/subject) on free and total testosterone levels PMID 28138310

The studies

Fenugreek extract has a significant effect on total serum testosterone.

PMID 32048383 · Effect of fenugreek extract supplement on testosterone levels in male: A meta-analysis of clinical trials. · Phytotherapy research, 2020

It can also interact with warfarin to cause bleeding.

PMID 30000838 · Fenugreek · Drugs and Lactation Database (LactMed), 2006

The deep dive on this

Early research

13Boron10 mg a day; frees what you haveEarly evidence

Boron

For: Free testosterone

A mineral that frees up more of the testosterone you already make. A small study, so keep expectations small.

What to do

  1. Take 10 mg a day with breakfast.
  2. Take nothing else new, and judge it on a blood test after 12 weeks.
How much
10 mg
When
With breakfast
How long
12 weeks alone, then test

Standard practice

10 mg a day is the standard adult upper limit.

What happened in the studies

More free testosterone

After a week at 10 mg a day, free testosterone rose and estrogen fell, in a study of 8 people.

¹ Journal of trace elements in medicine and biology, 2011. The study is under The science, below.

Watch out

A tiny one-week trial. Stay at the 10 mg it used.

The science
In detail
10 mg a day. One week moved free testosterone and dropped the binding protein and the estradiol in a study of eight; keep the expectations small.
Found
Free T up in one week, in 8 people. 10 mg a day for a week: the binding protein fell within six hours. By day seven free testosterone was up and estradiol down, with the inflammation markers lower.
Why
It appears to uncouple testosterone from the carrier protein that holds it, which fits the timing: hours, not weeks. It frees what you have; it makes none.
Watch
The trial had eight people and ran one week, and estradiol fell in it. Treat the number as a signal, and stay at the trial's dose.
The doses the studies used10 mg a day with breakfast: free testosterone up by day seven
10 mg

a capsule containing 10mg of boron PMID 21129941

The study

After one week (in samples taken at 8.00 A.M, only), the mean plasma free testosterone increased and the mean plasma estradiol decreased significantly.

PMID 21129941 · Comparative effects of daily and weekly boron supplementation on plasma steroid hormones and proinflammatory cytokines. · Journal of trace elements in medicine and biology, 2011

Six hours supplementation showed a significant decrease on sex hormone binding globulin (SHBG), high sensitive CRP (hsCRP) and TNF-α level.

The deep dive on this

14MagnesiumMagnesium, up to 400 mg a dayEarly evidence

Magnesium

For: Men who train hard

A mineral that sweat and training drain. Four weeks of it raised testosterone in a small trial.

What to do

  1. Take up to 400 mg of magnesium a day, with food.
  2. Keep it hours apart from antibiotics.
  3. Judge it on your next blood draw.
How much
Up to 400 mg
When
Daily, with food
How long
4 weeks, then test

Standard practice

UK advice: 400 mg or less a day of magnesium from supplements is unlikely to cause harm. More than 400 mg can cause diarrhea.

What happened in the studies

Free and total T up

In a 4-week trial, magnesium raised free and total testosterone, and more in those who trained.

¹ Biological trace element research, 2011. The study is under The science, below.

Watch out

Loose stools are common. Kidney disease: ask a doctor first. On antibiotics or blood-pressure medicine: ask a pharmacist about timing.

The science
In detail
The trial gave 10 mg of magnesium per kg of body weight (4.5 mg per lb) a day, for 4 weeks. For most men that is above the UK’s 400 mg a day line, so stay at 400 mg or less unless a doctor advises more. Judge it on your own draw.
Found
Free and total T up in 4 weeks. A 4-week controlled trial: magnesium raised free and total testosterone, in the active and the inactive alike. The rise was larger in those who trained.
Why
Magnesium runs hundreds of enzyme reactions, and sweat and hard training drain it. Topping up a low store is the proposed route.
Watch
Loose stools and stomach cramps, more at high doses. With kidney disease, not without a doctor, as it can build up. It blocks some antibiotics: take a quinolone such as ciprofloxacin hours apart from it, as its label sets out. It can add to the effect of blood-pressure medicine.
The doses the studies used10 mg per kg (4.5 mg per lb) a day, for 4 weeks, in the trial
10 mg per kg (4.5 mg per lb)

supplemented with 10 mg magnesium per kilogram body weight PMID 20352370

The study

Our results show that supplementation with magnesium increases free and total testosterone values

PMID 20352370 · Effects of magnesium supplementation on testosterone levels of athletes and sedentary subjects at rest and after exhaustion. · Biological trace element research, 2011

The increases are higher in those who exercise than in sedentary individuals.

The deep dive on this

15ForskolinForskolin extract, 250 mg twice a dayEarly evidence

Forskolin

For: Carrying extra fat

A plant extract. In a 12-week trial it raised free testosterone and cut body fat.

What to do

  1. Pick an extract standardized to 10% forskolin.
  2. 250 mg twice a day.
  3. Judge it on your blood draw at 12 weeks.
How much
250 mg
When
Twice a day
How long
12 weeks, then test

What happened in the studies

Free T up, fat down

In a 12-week trial of 30 people, forskolin raised free testosterone and cut body fat against placebo.

¹ Obesity research, 2005. The study is under The science, below.

Watch out

It can drop blood pressure and speed the heart. On blood-pressure medicine or a blood thinner, or before surgery: ask first. Buy a tested product.

The science
In detail
A Coleus forskohlii extract standardized to 10% forskolin, 250 mg twice a day, for 12 weeks, the trial’s dose. Judge it on your own draw.
Found
Free T up in 12 weeks. A 12-week placebo trial of 30 people: forskolin raised free testosterone against placebo and cut body fat and fat mass. Bone mass rose too.
Why
Forskolin raises cyclic AMP, the messenger that tells the testes to make testosterone when the brain signals, and that tells fat cells to release fat.
Watch
It can lower blood pressure and speed the heart: dizziness on standing, or palpitations. On blood-pressure medicine or a blood thinner, or before surgery, ask a doctor first. Stomach upset and loose stools in some. Buy a tested product: adulterated ones have been tied to liver injury.
The doses the studies used250 mg twice a day of a 10% forskolin extract, for 12 weeks, in the trial
250 mg twice a day

250 mg of 10% forskolin extract twice a day PMID 16129715

The study

Serum free testosterone levels were significantly increased in the forskolin group compared with the placebo group (p < or = 0.05).

PMID 16129715 · Body composition and hormonal adaptations associated with forskolin consumption in overweight and obese men. · Obesity research, 2005

Forskolin was shown to elicit favorable changes in body composition by significantly decreasing body fat percentage (BF%) and fat mass (FM) as determined by DXA compared with the placebo group (p < or = 0.05).

The sentence around it

…Results Forskolin was shown to elicit favorable changes in body composition by significantly decreasing body fat percentage (BF%) and fat mass (FM) as determined by DXA compared with the placebo group (p < or = 0.05).

16Mucuna pruriensMucuna seed powder, 5 g a dayEarly evidence

Mucuna pruriens

For: Trying for a child, with the doctor

A bean powder that carries L-dopa. In a small study it raised testosterone and improved sperm.

What to do

  1. Check the warnings: no MAO-inhibitor antidepressant.
  2. 5 g of seed powder a day.
  3. Judge it on your blood draw at 3 months.
How much
5 g
When
Daily
How long
3 months, then test

What happened in the studies

Testosterone up

In a small study, mucuna seed powder raised testosterone and LH, and sperm count and motility recovered.

¹ Fertility and sterility, 2009. The study is under The science, below.

Watch out

It carries L-dopa, a Parkinson’s medicine. Never with an MAO-inhibitor antidepressant, or within two weeks of stopping one. Ask a doctor first with glaucoma, melanoma or a skin growth not yet checked, a mental illness, diabetes, a stomach ulcer, an irregular heartbeat or a past heart attack, or if you take Parkinson’s medicine. Dizziness, nightmares and poor sleep are common.

The science
In detail
Mucuna pruriens seed powder, 5 g a day, for 3 months, the trial’s dose. It carries L-dopa, the Parkinson’s medicine, so read the warnings first. Judge it on your own draw.
Found
Testosterone and LH up. A before-and-after study of 75 people on treatment, against 75 controls: mucuna seed powder raised testosterone and LH and cut prolactin, and sperm count and motility recovered. A second study, 5 g a day for 3 months, found better sperm count and motility.
Why
Its L-dopa becomes dopamine in the brain. Dopamine lowers prolactin, and LH, the brain’s signal to the testes, rose with it.
Watch
It carries L-dopa. Not with an MAO-inhibitor antidepressant, or within two weeks of stopping one. Ask a doctor first with glaucoma, a history of melanoma or an undiagnosed skin growth, a mental illness, diabetes, a stomach ulcer, an irregular heartbeat or past heart attack, or on Parkinson’s medicine. Dizziness, nightmares and trouble sleeping are common L-dopa effects.
The doses the studies used5 g of seed powder a day, for 3 months, in the trial
5 g

M. pruriens seed powder (5 g day(-1)) orally PMID 18955292

The studies

Treatment with M. pruriens significantly improved T, LH, dopamine, adrenaline, and noradrenaline levels

PMID 18973898 · Mucuna pruriens improves male fertility by its action on the hypothalamus-pituitary-gonadal axis. · Fertility and sterility, 2009

Treatment with M. pruriens significantly ameliorated psychological stress and seminal plasma lipid peroxide levels along with improved sperm count and motility.

PMID 18955292 · Mucuna pruriens Reduces Stress and Improves the Quality of Semen in Infertile Men. · Evidence-based complementary and alternative medicine, 2010

17DHEADHEA, 50 mg or under, with a doctorEarly evidence

DHEA

For: Low draws, with a doctor

A hormone the body turns into testosterone. In pooled trials, the number rose a little.

What to do

  1. Ask the doctor first: it is a hormone.
  2. 50 mg a day or under, in the morning.
  3. Judge it on the next draw, testosterone and estrogen both.
How much
50 mg or under
When
Morning
How long
12 weeks, then test

Standard practice

In the UK, prasterone (DHEA) is a controlled drug, listed in Schedule 4, Part II, of the Misuse of Drugs Regulations 2001.

What happened in the studies

A small rise

Across 55 trial arms, testosterone rose after DHEA; in the subgroup that matches this page, by 21.36 ng/dL.

¹ Experimental gerontology, 2020. The study is under The science, below.

Watch out

Acne, oily skin and hair loss. It raises estrogen too. Prostate or breast trouble: doctor first.

The science
In detail
Early research, and a hormone: DHEA is made by the adrenal glands and turned into testosterone and estrogen. The pooled trials rose more above 50 mg a day. Stay at 50 mg or under, and only with a doctor watching your draws.
Found
Testosterone up 21.36 ng/dL. 42 trial reports, 55 arms: testosterone rose after DHEA in every subgroup. In the subgroup that matches this page, the rise was 21.36 ng/dL. The rise was bigger above 50 mg a day than at 50 or under.
Why
DHEA is a precursor: the body converts it into the sex hormones, so a dose tops up the raw material the testes and tissues use.
Watch
Androgenic side effects: acne, oily skin and hair loss. It raises estrogen as well as testosterone, so the draw checks both. With a hormone-sensitive condition, such as prostate or breast disease, not without a doctor.
The doses the studies used50 mg and under a rise of 19 ng/dL in the pooled trials
50 mg and underOver 50 mg

DHEA dosage of ˃50 mg/d compared to ≤50 mg/d (WMD: 57.96 ng/dl vs. 19.43 ng/dl) PMID 33045358

The study

testosterone level was significantly increased after DHEA administration (WMD: 28.02 ng/dl, 95% CI: 21.44-34.60, p = 0.00)

PMID 33045358 · A dose-response and meta-analysis of dehydroepiandrosterone (DHEA) supplementation on testosterone levels: perinatal prediction of randomized clinical trials. · Experimental gerontology, 2020

The sentence around it

…Results Overall results from 42 publications (comprising 55 arms) demonstrated that testosterone level was significantly increased after DHEA administration (WMD: 28.02 ng/dl, 95% CI: 21.44-34.60, p = 0.00).…

DHEA supplementation is effective for increasing testosterone levels, although the magnitude varies among different subgroups.

The sentence around it

…Conclusion DHEA supplementation is effective for increasing testosterone levels, although the magnitude varies among different subgroups.

The deep dive on this

With a doctor

Everything in this group is a decision for you and a doctor who has your history. It is here so you walk in knowing what to ask for.

18Weight loss with a GLP-1 medicineA GLP-1 medicine, if you carry extra fatEarly evidence

Weight loss with a GLP-1 medicine, if you carry extra fat

For: Carrying a lot of extra fat

A weekly shot from a doctor that turns hunger down, for a man with a lot of fat to lose. Testosterone rose as the weight came off.

What to do

  1. Only if you carry a lot of extra fat, on a prescription.
  2. Start at 0.25 mg a week; step up every 4 weeks.
  3. Keep lifting and keep the protein high.
  4. Judge it on your next blood draw.
How much
0.25 mg to 2.4 mg a week
When
Once a week
How long
Long term

Standard practice

Semaglutide starts at 0.25 mg once a week and steps up every 4 weeks to 1.7 or 2.4 mg. A step not tolerated waits 4 weeks. Heart rate is checked at regular intervals. Prescription only, in the UK and the US.

What happened in the studies

Testosterone up with the fat off

In seven pooled studies, testosterone rose on a GLP-1 medicine as the weight came off.

¹ World journal of methodology, 2026. The study is under The science, below.

Watch out

Boxed warning: thyroid tumors in rodents. Never with a personal or family history of medullary thyroid cancer or MEN 2, or after a serious allergy to it. A neck lump, trouble swallowing or a hoarse voice that lasts: tell the doctor. The dose climbs every 4 weeks. Severe belly pain that will not go, maybe into the back, can be pancreatitis: stop and get seen. Gallstones, low sugar with insulin or other diabetes pills, kidney injury if sickness dries you out, and severe gut side effects. Allergic swelling of the face or throat: emergency. Diabetic eye disease can worsen. Your resting heart rate rises: report a racing heart at rest. Tell anyone sedating you. The tablet can raise levothyroxine levels. Never share a pen. Sudden vision loss in one eye: urgent help. Keep lifting and keep the protein up, or muscle goes with the fat.

The science
In detail
If you carry a lot of extra fat and the draws are low, a GLP-1 medicine through a doctor takes the fat off faster than food alone, and testosterone rose with the loss. It is prescribed for obesity, or overweight with a weight-related condition. The usual start is semaglutide 0.25 mg a week, stepping up every 4 weeks to 2.4 mg. Keep lifting and keep the protein up, so the loss is fat. The other options and the full plan: Weight loss injections and surgery.
Found
Total testosterone up. Seven studies pooled: on a GLP-1 medicine, total testosterone rose, and the erection score went up 2.73 points. In four studies, the testosterone the body can use rose too.
Why
Fat tissue turns testosterone into estrogen and turns down the brain's signal to the testes. Taking the fat off lifts that brake, and the number follows the weight down.
Watch
The label's boxed warning: thyroid C-cell tumors in rodents. So never with a personal or family history of medullary thyroid cancer or MEN 2. A lump in the neck, trouble swallowing, breathlessness or a hoarse voice that lasts: tell the doctor. Never after a serious allergic reaction to it. The dose steps up every 4 weeks. If a step is not tolerated, the next is delayed 4 weeks. Severe gut side effects, and not with severe gastroparesis. Pancreatitis: severe belly pain that will not go, sometimes into the back, means stop it and get seen. Gallstones and gallbladder inflammation. Low blood sugar with insulin or a sulfonylurea. Kidney injury when sickness or diarrhea dries you out. Anaphylaxis and swelling of the face or throat. Diabetic eye disease can get worse. The resting heart rate rises, so it is checked at regular intervals. A racing heart at rest: tell the doctor. Food can stay in the stomach under anesthesia or deep sedation: tell the team before any procedure. The tablet form raised levothyroxine levels 33%. Never share a pen. A sudden loss of vision, usually in one eye: get urgent help. Muscle goes with the fat unless you keep lifting and keep the protein high.

The studies

A significant increase was found regarding TT, SHBG, and FSH, MD 73.04, 95%CI: 16.91-129.17, MD 7.00, 95%CI: 1.71-12.30, and MD 0.46, 95%CI: 0.01-0.91 respectively.

PMID 42626264 · Glucagon-like receptor-1 agonists and impotence: A meta-analysis. · World journal of methodology, 2026

GLP-1 RA use was significantly associated with increased bioavailable testosterone

PMID 41291666 · Effect of GLP-1 agonists on testosterone levels: a systematic review and meta-analysis. · BMC urology, 2025

The sentence around it

GLP-1 RA use was significantly associated with increased bioavailable testosterone (MD -57.18; 95% CI -87.60 to -26.76; p < 0.001; I 2 = 86%) and decreased HbA1c (MD 0.79; 95% CI 0.58 to 1.00; p < 0.001; I 2 = 0%).…

19Testosterone therapy, if the draws stay lowTestosterone therapy, when both draws stay lowStrong evidence

Testosterone therapy, if the draws stay low

For: Both draws low, with symptoms

Testosterone from a doctor, only when two tests and the symptoms agree. It brings the number back into the normal range.

What to do

  1. Only after two low draws, the symptoms and the cause tests.
  2. Trying for a child? Say so first: it stops sperm production.
  3. Your doctor sets the dose and checks the blood count and the prostate.
  4. Leg pain and swelling, or sudden breathlessness: stop and get seen.
How much
Doctor-set
When
As prescribed
How long
Ongoing

Standard practice

On the gel, blood pressure is measured periodically, and children keep off the skin where it went on.

What happened in the studies

Back into range

In 17 trials, testosterone treatment improved sexual function against placebo. In 59 trials, fat fell and lean mass rose.

¹ The lancet. Healthy longevity, 2023. The study is under The science, below.

Watch out

It can suppress sperm production. Blood pressure, red blood cells and the risk of blood clots can rise. It is ruled out by breast or prostate cancer, and the prostate is checked. It can worsen sleep apnea, cause swelling and grow breast tissue. It is not established for low testosterone that comes with age. In the biggest safety trial, an irregular heartbeat, kidney injury and lung clots were more common on it. Boxed warning on the gel: children and women must not touch the skin where it went on; cover it and wash your hands. It can be abused and can cause dependence.

The science
In detail
If both draws stay low with the symptoms, after the habits and a search for the cause, testosterone therapy through a doctor puts the number back into the normal range. It shuts down sperm production, so trying for a child comes first. The full detail: TRT. UK and US: prescription only.
Found
Sexual function up 5.52 points. Pooled data from 17 trials: testosterone treatment raised the sexual function score by 5.52 points against placebo. 59 trials: fat down and lean mass up. The biggest safety trial dosed a daily 1.62% gel to 350 to 750 ng/dL.
Why
It replaces the hormone directly, so the number rises whatever the cause. That is also why the testes' own output, and sperm, go quiet on it.
Watch
The label: sperm production can be suppressed. Red cell count and blood pressure can rise, and blood clots in the legs and lungs have been reported. The prostate is checked before and during treatment, and breast or prostate cancer rules it out. It can worsen sleep apnea, cause fluid retention and grow breast tissue. Its safety and benefit in age-related low testosterone are not established. On the gel, children and women must not touch the skin where it went on. In the biggest safety trial, atrial fibrillation, kidney injury and clots in the lung were more common on testosterone. It has been abused at high doses, with serious heart and mental-health harms, and the label lists dependence.
The doses the studies used1.62% gel, to 350 to 750 ng/dL the safety trial's dose: adjusted to the mid-normal range
1.62% gel, to 350 to 750 ng/dL

daily transdermal 1.62% testosterone gel (dose adjusted to maintain testosterone levels between 350 and 750 ng per deciliter) PMID 37326322

The studies

Compared with placebo, testosterone treatment increased 15-item International Index of Erectile Function (IIEF-15) total score (mean difference 5·52 [95% CI 3·95-7·10]

PMID 37804846 · Symptomatic benefits of testosterone treatment in patient subgroups: a systematic review, individual participant data meta-analysis, and aggregate data meta-analysis. · The lancet. Healthy longevity, 2023

The sentence around it

Compared with placebo, testosterone treatment increased 15-item International Index of Erectile Function (IIEF-15) total score (mean difference 5·52 [95% CI 3·95-7·10]; τ 2 =1·17; n=1412) and IIEF-15 erectile function subscore (2·14 [1·40-2·89]; τ 2 =0·64; n=1436), reaching the minimal clinically important difference for mild erectile dysfunction.…

TS was associated with a significant reduction in fat and with an increase in lean mass as well as with a reduction of fasting glycaemia and insulin resistance.

PMID 26537862 · THERAPY OF ENDOCRINE DISEASE: Testosterone supplementation and body composition: results from a meta-analysis study. · European journal of endocrinology, 2016

The deep dive on this

How you'll know it's working

Track
Total and free testosterone
How to track
Two fasting blood draws between seven and ten in the morning, a few days apart, before you change anything. Then one every twelve weeks.
When to judge
The habits are judged on the week-12 draw. After that, each supplement runs alone and the next draw judges it.

Why this happens

You have read that your testosterone is low, or you feel like it is: less drive, softer, tired by three. Before a prescription, the question is what your own body can do.

The signal

The pituitary sends LH, and LH tells the testicle to make testosterone. Short sleep, heavy drinking and belly fat all turn that signal down; opioids, steroid tablets and hormones from outside switch it off. Fix what turns it down and the testicle does the rest.

The testicle's output

The testicle builds testosterone from cholesterol, with zinc in its enzymes. Fat kept in the diet and enough zinc keep that line supplied. Tongkat ali and shilajit raised total testosterone in their trials: the output itself.

The free fraction

Most testosterone in the blood is bound to a carrier protein and does nothing. Boron loosened that grip within hours in its trial, so more of what you already make is free to work.

7 to 8 h sleep, regularBody fat downAerobic work, if heavyOver 4 US standarddrinks (7 UK units) aweekOpioids, steroid tabletsLH from the pituitarydrives the testicleZinc, if lowFat kept in the dietTongkat ali, shilajitThe testicle makes moreBoron 10 mgBinding protein loosensits gripYour owntestosteroneupYour owntestosteroneupYour owntestosteroneupYour owntestosteroneupThe signalThe testicle's outputThe free fraction7 to 8 h sleep, regularBody fat downAerobic work, if heavyOver 4 US standard drinks (7 UKunits) a weekOpioids, steroid tabletsLH from the pituitary drivesthe testicleZinc, if lowFat kept in the dietTongkat ali, shilajitThe testicle makes moreBoron 10 mgBinding protein loosens itsgripYour own testosterone upYour own testosterone upYour own testosterone upYour own testosterone upThe signalThe testicle's outputThe free fraction
Figure 2. How the moves lead to your own testosterone up. The dotted orange boxes are the things to cut back.

Week by week

Why this order

The habits first, then one supplement at a time, each judged on its own draw.

04812162024283236404448Weeks from the startThe two drawsThe habitsZinc, only if lowTongkat ali, aloneShilajit, aloneThen one more, aloneLow with symptoms: a doctorReview, week 12081624324048Weeks from the startThe two drawsThe habitsZinc, only if lowTongkat ali, aloneShilajit, aloneThen one more, aloneLow with symptoms: a doctorReview, week 12
Figure 3. The plan by week: navy bars keep going, orange bars are the moves you add, white bars are checks and decisions. The starburst marks the review at week 12.
WhenAddWhy then
Week 0Two morning draws, a few days apart, before you change anything. Total testosterone and SHBG both times; LH, FSH, HbA1c, ferritin and zinc on the first; prolactin if LH is low. The list of what you take. Both low with symptoms, or any warning sign: the doctor now.The confirmed baseline every later move is judged against.
Weeks 1 to 12The habits: sleep, drink, the belly with the fat kept in, and aerobic work if you carry extra weight. Zinc only if the draw said low.They move the number most, and they go first so the draw can judge them.
Week 12, the re-testThe same draw, same lab, same hour. This draw judges the habits. Up: keep going. Still low, with symptoms: the doctor, with all three numbers.Twelve weeks is where the number shows.
Weeks 12 to 24Tongkat ali, 200 mg a day. Nothing else new. Draw again at week 24.One change at a time, so the draw can tell you what worked.
Weeks 24 to 36If you want more: shilajit for ninety days, alone, then a draw.The same rule: one change, one draw.
After thatAshwagandha, fenugreek or boron, one at a time, each for its trial's length, each with a draw after. Then, if you want the early research, magnesium, forskolin or mucuna, the same way.The narrower claims last.

What to track

One number: total and free testosterone, from a fasting morning draw. Two draws at the start, then one every twelve weeks, because the number swings by the day.

The diary is how you know which move did it. Sleep and drinks every day; the supplement you are on; your energy out of ten.

The diary, one week

DaySleep (h)DrinksSupplement takenEnergy 1 to 10What changed
Mon     
Tue     
Wed     
Thu     
Fri     
Sat     
Sun     
  • Total testosterone: the target is a re-test above the baseline, on the same lab, at the same hour.
  • Free testosterone: calculated from the total and SHBG. Boron moves it when the total does not.
  • Zinc: test once; supplement only if low; stop after six months.
  • Warning signs, a doctor now: headaches, vision change, milky nipple discharge, breast growth.

Doses at a glance

The amounts the studies used, move by move. The label or your doctor sets your dose.

MoveWhat the studies usedWhenHow longStudy
1. Check what you takeA list of what you takeBefore the first drawOncePMID 27532478
2. Trying for a child: tell the doctorTell the doctor firstBefore anything for testosteroneWhile tryingPMID 39820213
3. Sleep7 to 8 hours asleepThe same times, seven daysAlwaysPMID 34801825
4. Body fat downSlow, steady fat lossUntil the belly is gone12 weeks, then the drawPMID 23482592
5. Keep the fat in the dietFat kept in the dietEvery mealFor goodPMID 33741447
6. Aerobic training, if you carry extra weightRegular aerobic trainingMost weeks12 weeks, then the drawPMID 39467940
7. Drinking less without quittingUnder four US standard drinks (seven UK units) a weekNone most nightsEvery weekPMID 37159717
8. Tongkat Ali200 mg standardized water extractDaily1 month in the trial; judge it on a draw after 12 weeks alonePMID 36013514
9. ZincAbout 30 mg a day as zinc gluconateWith food3 to 6 months, then stopPMID 36577241
10. Shilajit250 mg, twice a dayMorning and evening90 daysPMID 26395129
11. Ashwagandha21 mg withanolide glycosidesDaily8 weeks in the trial; judge it on the next drawPMID 41740946
12. Fenugreek500 mg seed extractDaily12 weeks, then the drawPMID 32048383
13. Boron10 mg a dayWith breakfast1 week in the trial; judge it on a draw after 12 weeks alonePMID 21129941
14. MagnesiumUp to 400 mg a day; 10 mg per kg (4.5 mg per lb) in the trialDaily, with food4 weeks in the trial; judge on the drawPMID 20352370
15. Forskolin250 mg of 10% extract, twice a dayTwice a day12 weeks in the trialPMID 16129715
16. Mucuna pruriens5 g seed powder a dayDaily3 months in the trialPMID 18973898
17. DHEA50 mg a day or underMorning12 weeks, then the drawPMID 33045358
18. Weight loss with a GLP-1 medicine, if you carry extra fatSemaglutide 0.25 mg a week to start; 2.4 mg to keepOnce a weekSteps every 4 weeks; judge on the next drawPMID 42626264
19. Testosterone therapy, if the draws stay lowDoctor-set, on the blood testsDaily, as prescribedOngoingPMID 37804846

Deep dives

The studies

Every study behind this page, newest first.

Words on this page

Standardized mean difference (SMD)
A way to put results measured on different scales onto one scale. About 0.2 is a small effect, 0.5 medium and 0.8 large.
95% CI
The range the true result probably sits in. The narrower the range, the surer the result.
Meta-analysis
Many studies pooled into one result.
RCT
A randomized controlled trial: people put by chance on the treatment or on a dummy version.
PMID
A study's ID number in PubMed, the public index of medical research.
Strong, moderate and early evidence
Strong: many human trials agree. Moderate: human studies point the same way. Early: the first small human studies.
Total and free testosterone
Total is everything in the blood; most of it is bound to a carrier protein and inert. Free is the fraction that works. The draw on this page asks for both.
SHBG
Sex hormone binding globulin, the carrier protein. Less of it means more free testosterone from the same total.
ng/dL and nmol/L
The two units labs report testosterone in. Divide ng/dL by 28.8 to get nmol/L; 300 ng/dL is about 10.4 nmol/L.
Hypogonadism
The medical word for a testosterone that is low twice, with the symptoms. The guidelines diagnose on the number and the symptoms together, never the number alone.
LH and FSH
The two pituitary hormones that run the testicle: LH for testosterone, FSH for sperm. Testosterone from outside switches both off.
Standardized mean difference (SMD)
An effect in units of spread, so trials with different scales can be pooled. About 0.2 is small, 0.5 medium, 0.8 large.
Unit of alcohol
The measure the drinking studies count in: 10 mL, or 8 g, of pure alcohol. A single measure of spirits is one; a pint of ordinary beer is about two.
Prolactin
A pituitary hormone. Too much of it turns the testosterone signal down; the draw adds it when LH is low.
HbA1c and ferritin
HbA1c is average blood sugar over about three months; ferritin is the body's iron store. Diabetes and iron overload both sit behind some low results.

Get the two draws, fix sleep, drink and the belly, then add one supplement at a time, each judged on its own draw. If the number stays low, walk into the doctor with the numbers.

When to see a doctor
  • Your first result is very low: under 150 ng/dL (5.2 nmol/L).
  • You have new headaches, or your vision or side vision has changed.
  • You have discharge from a nipple, milky or not.
  • Your breasts are growing, sore, or have a lump.
  • Your testes are small.
  • You are trying for a child. Tell the doctor before you take anything for testosterone.
  • Your LH comes back low or low-normal: prolactin is the next test, read by a doctor.
  • Both morning draws are under 300 ng/dL and you have the symptoms.

I am not a doctor. This is not medical advice. This is self-education. Every dose on this page is the dose a trial used, quoted from the trial; it is not a prescription. Talk to a physician who has your bloodwork before you change a medication and before anything in the With a doctor group.