Men's hormone health · Australia & New Zealand
Exhausted, flat, and told you're fine?
Kelo reads your blood results properly and finds what is actually dragging you down — sleep, weight, a real deficiency, or something that needs a doctor. Most men put up with it for years. You don't have to.
Sound familiar?
These are the moments men describe when their hormones are off — in their own words, from published research. Most are told it's age, or stress, or that their bloods look normal. Most never ask again.
None of this is a character flaw. Some of it is measurable.
Find out what's going onPhotographs are AI-generated illustrations of situations, not clients. Quoted lines are verbatim from men with low testosterone taking part in published research (Aceves-Martins et al., Andrology, 2022) and are not attributed to anyone pictured. Figures: Ten to Men longitudinal study, University of Canberra (Archives of Sexual Behavior, 2025); Australian Study of Health and Relationships (Richters et al.); Healthy Male.
What you actually receive
Most of this category sells you a PDF and a motivational voice note. Here is the actual work product — what lands in your inbox, and what it looks like twelve weeks later.
Ranked by effect size in published research
Total testosterone, nmol/L · shaded band is the published adult male range
Illustrative example only. Not a typical result and not a promised one — starting points and causes differ, and some men find the cause needs a doctor rather than a coach.
| Total testosterone | 11.2 | in range |
| Free testosterone | 0.19 | low |
| SHBG | 58 | high |
| LH | 4.1 | in range |
| 25-OH vitamin D | 41 | low |
| Ferritin | 96 | in range |
“Your total looks fine. Your SHBG is high, which is why your free is not — that is the number your symptoms track, and it is the one we work on.”
Adjusted every week on your check-in, not written once and forgotten.
How Kelo works
What holds you steady is below the waterline.
You can't see testosterone, sleep debt or a deficiency. You can measure them. That is where we start.
How Kelo works
Almost everyone in this category sells one thing and implies it fixes everything. We run two, they work on different timelines, and we are precise about which one does what.
A proper blood panel, then systematically correcting whatever is actually suppressing you — sleep debt, body fat, a genuine deficiency, alcohol, untreated sleep apnoea, or something already sitting on your medication list.
Structured pelvic floor training — contraction and relaxation both. An over-tight pelvic floor causes its own problems, which is exactly why unguided kegels picked up off the internet so often make things worse.
The two levers pay out at different times. That is not a scheduling detail — it is the whole reason we run them together.
The function lever is what carries you through the first month, while the hormone lever is still working. Run the hormone lever alone and week six feels like nothing is happening, because on most panels nothing measurable has happened yet.
Where we stand
This is a category built on urgency, before-and-after photos and supplements nobody needs. Here is what Kelo will not do, and why each one costs us money.
A University of Sydney analysis of 46 high-reach testosterone posts, reaching 6.8 million followers, found not one cited any scientific evidence. Every claim we make carries a named source.
The moment we stock something, every recommendation is contaminated by what is in the warehouse. If magnesium is what you need, buy it at the supermarket.
For most men the biggest lever is sleep or body composition, and both are free. If that is your situation we say so rather than sell you twelve weeks.
How this actually works
No portal, no app to download, no account to create. Send your blood results to the same WhatsApp thread you'll be coached in — and it stays there, so you can scroll back to anything we said in week two.
Replies during Australian and New Zealand hours. No number is published for a reason — chat keeps a record you both can see.
You'll be messaging Kelo, a verified WhatsApp Business account.
Where to start
The free tools are genuinely free and genuinely useful. Use them whether or not you ever pay us anything.
Fourteen questions about how you actually live, scored against published effect sizes. You get a ranked list of what is most likely working against you, and a sheet to take to your GP.
Start the assessment Free toolTotal testosterone alone tells you very little — most of it is bound and unavailable. Enter three numbers from your panel and get calculated free and bioavailable testosterone, in nmol/L or ng/dL.
Open the calculator Free toolAustralian and New Zealand laboratories report in nmol/L. Almost everything you will read online is in ng/dL. Convert between them and see where your number actually sits.
Convert a result A$297 · four weeksOne blood panel, one long call, and a written protocol built around what your results actually say. For a lot of men this is enough on its own.
See what is included A$1,497 · twelve weeksThe full programme. Weekly check-ins, direct access, a plan built around your panel, and a retest at the end so you can see whether any of it worked.
See what is included Read firstTen situations where we will not take your money, and where to go instead. Worth two minutes before you buy anything from anyone in this category.
Read the listThe Kelo Report
Upload the report your laboratory gave you. Within 24 hours you get it back translated — every marker in plain language, your free testosterone calculated, and a ranked list of what is most likely working against you.
Programmes
Genuinely — most men should start with the Baseline. If it turns out you need the longer programme, the A$297 comes off the price. If it turns out you do not, you have saved A$1,200 and still know what to do.
For men who have never actually measured any of this.
For men who want it sorted rather than understood.
Prices in Australian dollars; New Zealand customers are charged in NZD at checkout. Blood panels are ordered by you, directly from a laboratory, and are not included — budget roughly A$150–300 depending on the panel. Kelo is a coaching service, not a medical practice.
12-Week Protocol
Twelve weeks, built around your own blood panel rather than a generic stack. We work out which of your habits is costing you most, change those first, and retest at the end so you can see whether it worked.
Not sure? Read who this is not for — it's a longer list, and we would rather you didn't buy than buy the wrong thing.
We go through it line by line — total and free testosterone, SHBG, LH, FSH, vitamin D, ferritin, thyroid, HbA1c. Most men have never had anyone explain one to them.
Which of sleep, body fat, alcohol, training, stress or a genuine deficiency is costing you most — weighted by the size of the effect in published research, not by what we happen to sell.
Built around what you already eat and what your panel says is missing. Grocery lists included, because the plan you have to think about is the plan you abandon.
The single largest lever in the research. Eight nights at five hours dropped testosterone 10–15% in healthy young men — no supplement moves it that far in either direction.
Compound lifting, progressively loaded, scaled to what you can actually recover from. More training is not better past a point, and for a lot of men it is the problem.
Contraction and relaxation both. This is the lever that moves erections and ejaculatory control, usually inside four to twelve weeks — and it works on a completely separate track to the hormone side.
Only what your panel shows is low, at a sensible dose, retested. We do not sell supplements, and we do not stock tribulus or D-aspartic acid — both have failed repeatedly in human trials.
One person, who knows your file. Not a ticket queue and not a chatbot. Message your coach when something comes up, and you get an answer from the person who actually built your plan.
Twelve of them. This is where the plan gets adjusted to what is actually happening rather than what we assumed in week one.
What moved, what did not, and what we would do next — whether or not that involves working with us again.
Every guide and programme, yours permanently, including the ones released after you finish.
You order the panel through the link we give you, or through your GP if you prefer. Results come back to you. We book a call as soon as they land.
We go through the panel together, work out which drivers are costing you most, and build the twelve weeks around those. Weekly check-ins, direct access in between.
Same panel, same conditions, twelve weeks later. This is the part almost nobody does, and it is the only way to know whether any of it worked.
Do the work for twelve weeks and log it. If your retest shows nothing moved, you keep working with us at no further cost until it does. Anyone guaranteeing you a specific testosterone figure in advance is guessing — they cannot know your starting point, your cause, or your biology. What we can promise is that we are still here if the first attempt does not land.
Conditions: the protocol logged at least five days a week, both blood panels completed at the times specified, and check-ins attended. This covers continued coaching, not a cash refund, and not the cost of your blood tests.
The difference between those two is one blood test and the willingness to change a few things properly. Places are limited because the access is direct — one coach, a small number of men at a time.
Nobody knows, and anyone who tells you otherwise is guessing. For context, 1,000 ng/dL is 34.7 nmol/L — above the top of the standard adult reference range, not in the middle of it. Some men get there. Most reach their own ceiling, which is the number that actually matters. If a guaranteed figure is what you are shopping for, someone will happily sell you one.
No, and we are careful about that line. Kelo coaches on food, sleep, training, alcohol, stress and pelvic floor — none of which needs a medical degree, and all of which is where the effect actually is. If your results or symptoms need a doctor, we say so plainly and refer you rather than take your money.
No. You order it yourself so the results belong to you rather than to us, and so you can keep testing long after we stop working together. We tell you exactly what to order and how to time it — morning, fasted, and repeated — because a badly timed panel is worse than none.
Then this is not for you, and we will not take the booking. We do not prescribe or adjust hormone therapy, so we would be a second opinion without any of your history. Your prescriber is the right person.
Because that is roughly how long the hormone side takes to show up on a panel, and retesting sooner tells you very little. The pelvic floor work usually shows up much earlier, around week four, which is deliberate — it is what carries you through the stretch where nothing measurable has happened yet.
Then save your money. The changes that move testosterone are sleep, body composition and alcohol, and none of them happen in the margins of a week you are not willing to change. We would rather tell you that now than take A$1,497 and watch it not work.
Kelo is a coaching and education service, not a medical practice. Nothing here is medical advice, diagnosis or treatment. Nothing here replaces your GP, and if your results or symptoms need medical attention we say so and refer you. Where a link earns a commission, it is disclosed.
What you actually receive
Most of this category sells you a PDF and a motivational voice note. Here is the actual work product — what lands in your inbox, and what it looks like twelve weeks later.
Ranked by effect size in published research
Total testosterone, nmol/L · shaded band is the published adult male range
Illustrative example only. Not a typical result and not a promised one — starting points and causes differ, and some men find the cause needs a doctor rather than a coach.
| Total testosterone | 11.2 | in range |
| Free testosterone | 0.19 | low |
| SHBG | 58 | high |
| LH | 4.1 | in range |
| 25-OH vitamin D | 41 | low |
| Ferritin | 96 | in range |
“Your total looks fine. Your SHBG is high, which is why your free is not — that is the number your symptoms track, and it is the one we work on.”
Adjusted every week on your check-in, not written once and forgotten.
4-Week Baseline
Four weeks. One blood panel, one long call, and a starting protocol built around what your results actually say instead of what a generic article guessed. For a lot of men this is enough on its own.
Not sure? Read who this is not for — it's a longer list, and we would rather you didn't buy than buy the wrong thing.
Line by line — total and free testosterone, SHBG, LH, FSH, vitamin D, ferritin, thyroid, HbA1c. What each one is, and what yours says.
The request sheet plus the timing rules that most men get wrong — morning, fasted, off biotin, not after a heavy session, and repeated before drawing conclusions.
Which of sleep, body fat, alcohol, training, stress or a genuine deficiency is most likely costing you — weighted by effect size in published research.
Sleep, food, alcohol, training and pelvic floor, prioritised for your results. Specific enough to follow without us.
You will not remember all of it. Rewatch whenever you like.
Including, often, that you do not need to pay us anything further — or that what you have described needs a doctor rather than a coach.
You order the panel through the link we give you, or through your GP. We tell you exactly what to ask for and how to time it. Results come back to you.
A 45-minute call going through your panel line by line, plus your assessment. What each marker means, which of them matter for you, and which are noise.
You leave with a written protocol covering sleep, food, alcohol, training and pelvic floor, prioritised for your results. Yours to keep and repeat.
No forms and no argument. We would rather refund a man who learned nothing than keep A$297 and have him tell people it was worthless. That offer stands for fourteen days after the call.
Refund covers the A$297 coaching fee. It does not cover the cost of your blood panel, which you paid to the laboratory directly and which remains yours either way.
Most men have never had anyone sit down and explain their own bloodwork to them. Start there, and decide what you want to do afterwards.
No. You order it yourself so the results belong to you, and so you can keep testing long after we stop talking. Budget roughly A$150–300 depending on the panel and the provider.
No. You get the full read, the written protocol and the recording whether or not you ever speak to us again. If we think you do not need the 12-week programme we say so — that happens often, and it is the reason people send us their friends.
Yes. If you move to the 12-Week Protocol within 60 days, the A$297 comes off the price.
No, and nobody here claims to be. Kelo coaches on food, sleep, training, alcohol, stress and pelvic floor — none of which needs a medical degree, and all of which is where the effect actually is. If your results need a doctor, we say so and refer you.
Kelo is a coaching and education service, not a medical practice. Nothing here is medical advice, diagnosis or treatment. Nothing here replaces your GP, and if your results or symptoms need medical attention we say so and refer you. Where a link earns a commission, it is disclosed.
What you actually receive
Most of this category sells you a PDF and a motivational voice note. Here is the actual work product — what lands in your inbox, and what it looks like twelve weeks later.
Ranked by effect size in published research
Total testosterone, nmol/L · shaded band is the published adult male range
Illustrative example only. Not a typical result and not a promised one — starting points and causes differ, and some men find the cause needs a doctor rather than a coach.
| Total testosterone | 11.2 | in range |
| Free testosterone | 0.19 | low |
| SHBG | 58 | high |
| LH | 4.1 | in range |
| 25-OH vitamin D | 41 | low |
| Ferritin | 96 | in range |
“Your total looks fine. Your SHBG is high, which is why your free is not — that is the number your symptoms track, and it is the one we work on.”
Adjusted every week on your check-in, not written once and forgotten.
The panel
You order this yourself, from a laboratory, and the results come back to you. Here is what every marker is for — including the three that most people leave off and then cannot interpret anything without.
The headline number, and the least useful one on its own. Ask for mass spectrometry rather than immunoassay — immunoassay is unreliable at exactly the low end you would be trying to measure.
What it does not show:
Harmonised adult male reference range roughly 9.2–31.8 nmol/L (264–916 ng/dL).
Most of your testosterone is bound to these and unavailable to tissue. Without them you cannot calculate free testosterone, which is why a total-only result explains so little. Rising SHBG with age can leave total looking fine while free drops.
What it does not show:
The most important markers on the panel and the most commonly omitted. Low testosterone with low or normal LH points upstream to the brain — often reversible. Low testosterone with high LH points to the testes, which is not something coaching fixes and needs a specialist.
What it does not show:
Testosterone converts to oestradiol via aromatase, largely in fat tissue. Useful context for symptoms and for understanding why body composition matters so much here.
What it does not show:
Elevated prolactin alongside low LH and low testosterone can indicate a pituitary problem that needs imaging rather than a lifestyle programme. This is one of our hard referral triggers.
What it does not show:
One of the few nutrients where correcting a genuine deficiency has reasonable support. Worth measuring precisely because supplementing when you are already replete does nothing.
What it does not show:
Iron overload is a genuine and reversible cause of low testosterone, and it is easy to miss. It is also why we will never tell you to take iron without measuring first.
What it does not show:
Insulin resistance suppresses testosterone and tracks closely with body composition. Frequently the most useful number on the whole panel for deciding what to do first.
What it does not show:
Thyroid dysfunction produces almost exactly the symptom list people arrive with — fatigue, low mood, poor recovery, low libido. Worth excluding before assuming the cause is androgenic.
What it does not show:
General safety and a baseline haematocrit. Haematocrit above 0.54 is one of our referral triggers.
What it does not show:
If you are over 40 or have a family history. An abnormal result is a referral, not a coaching input.
What it does not show:
Reference ranges differ between laboratories; always read the range printed on your own report. Australian and New Zealand labs report testosterone in nmol/L. Educational information only, not medical advice.
The evidence
Graded honestly, including the ones where the evidence is weak and the ones where it points against something we could have sold you. Where a finding failed to replicate, that is on the page too.
Eight nights restricted to five hours lowered daytime testosterone by 10–15% in healthy young men. This is the largest effect of any single lifestyle factor we work with, and it is free.
What it does not show: That extending sleep beyond a normal night raises testosterone above normal. It removes a suppressor; it is not a booster.
Leproult R, Van Cauter E. JAMA 2011;305(21):2173–2174.
Adipose tissue contains aromatase, which converts testosterone to oestradiol. Weight loss consistently raises total testosterone in men with obesity, and it is the largest modifiable factor in the literature.
What it does not show: That it helps lean men. If body fat is not elevated, this lever is not available to you.
Consistent across multiple randomised trials and meta-analyses.
Sleep apnoea fragments the night-time architecture most testosterone release depends on. It is common, very treatable, and routinely missed — which is why our assessment screens for it.
What it does not show: That treating apnoea reliably normalises testosterone on its own. It removes an obstacle.
Luboshitzky R et al. J Clin Endocrinol Metab 2002.
One year of 3,332 IU/day was associated with roughly a 25% rise in a 2011 trial. Later randomised trials in men who were already replete found no effect on testosterone at all. Our reading: correcting a genuine deficiency may help, and supplementing when you are not deficient does nothing.
What it does not show: That vitamin D raises testosterone in men with normal levels. The replication attempts were null.
Pilz S et al. Horm Metab Res 2011 (positive); Lerchbaum E et al. 2017, 2019 (null in replete men).
Experimentally induced marginal zinc deficiency substantially reduced testosterone in young men, and repletion restored it. This is a repair mechanism, not an enhancement one.
What it does not show: That extra zinc helps anyone who is not deficient. Chronic high intake causes copper deficiency.
Prasad AS et al. Nutrition 1996;12(5):344–348.
A modest increase in total and free testosterone was reported with supplementation, with a larger effect in men who were exercising. We use it mostly for sleep quality, which is the better-established mechanism.
What it does not show: A large or reliable direct hormonal effect. Treat it as a sleep intervention.
Cinar V et al. Biol Trace Elem Res 2011;140(1):18–23.
In overweight, fatigued men, 8 weeks of standardised extract was associated with roughly a 15% increase in testosterone and an 18% increase in DHEA-S. The better-evidenced herbal option, and also the one with the most real safety signal — see our safety page before taking it.
What it does not show: Long-term safety, or an effect in healthy non-fatigued men. Liver injury case reports exist.
Lopresti AL et al. Am J Mens Health 2019;13(2). Also Wankhede S et al. 2015.
In men with late-onset hypogonadism, supplementation was associated with normalisation of testosterone in a large proportion of participants. Better trial support than most herbals in this category.
What it does not show: Product quality is the weak point, not the mechanism — heavy-metal contamination has been found in market samples.
Tambi MIBM et al. Andrologia 2012;44 Suppl 1:226–230.
In a randomised trial, pelvic floor muscle training outperformed lifestyle advice alone for erectile dysfunction, with a substantial proportion regaining normal function by six months. It also has support for ejaculatory control.
What it does not show: Any effect on serum testosterone. There is no good evidence it raises it, and we say so on every page where we mention it.
Dorey G et al. BJU International 2005;96(4):595–597.
Longitudinal data show total testosterone falling roughly 1% per year from around age 40, with free testosterone falling faster because SHBG rises with age. This is why we track free testosterone rather than total alone.
What it does not show: That the decline is a disease requiring treatment. It is a normal trajectory.
Feldman HA et al. Massachusetts Male Aging Study. J Clin Endocrinol Metab 2002;87(2):589–598.
Repeatedly tested in humans and repeatedly negative, including in trained men. It remains one of the most-sold ingredients in this category, which tells you something about the category.
What it does not show: —
Multiple randomised controlled trials; consistently null for serum testosterone.
An early positive study drove its popularity. Subsequent trials failed to replicate it, and at higher doses testosterone decreased in resistance-trained men.
What it does not show: —
Melville GW et al. J Int Soc Sports Nutr 2015;12:15.
Summaries are ours and are necessarily simplified; where a study matters to a decision you are making, read it yourself rather than taking our word for it. Educational information only, not medical advice.
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Free assessment
Fourteen questions about how you live, scored against the research. You'll get a ranked list of what's most likely working against you, and a sheet to take to your GP.
Answers stay in your browser until you choose to send them. No account needed.
We've stopped the assessment here deliberately. We're not going to sell you a programme when what you've described needs proper medical assessment first. Please book with your GP, and take this with you:
If you're in immediate distress, in Australia call Lifeline on 13 11 14. In New Zealand, call or text 1737.
We've stopped the assessment here on purpose. Kelo coaches men on food, sleep, training and recovery — we are not doctors, and what you've described needs one. So we are not going to show you a programme or take your money. Book with your GP, and take this with you.
Your report
Ranked by how much each factor moved testosterone in published research, adjusted for what you told us. This describes your habits, not your hormones — only a blood test does the second one.
Ask for these on a morning blood draw. Print it, or photograph it.
Free tool
Total testosterone on its own tells you very little. Most of it is bound to SHBG and unavailable to your tissues. Enter three numbers from your blood panel to calculate free and bioavailable testosterone using the Vermeulen equation.
Enter your total testosterone and SHBG to calculate free and bioavailable testosterone.
Everything is calculated in your browser. Nothing is sent anywhere or stored.
This uses the Vermeulen equation (Vermeulen A, Verdonck L, Kaufman JM, J Clin Endocrinol Metab 1999;84:3666–72), the method most widely used for calculated free testosterone. It solves the law-of-mass-action equilibrium between testosterone, SHBG and albumin, using association constants of KSHBG = 1.0 × 109 L/mol and Kalb = 3.6 × 104 L/mol, with albumin taken as 69,000 g/mol and testosterone as 288.42 g/mol.
Calculated free testosterone tracks equilibrium dialysis (the reference method) closely and is far more reliable than direct analogue free-testosterone immunoassays, which are not recommended. The reference range shown is the CDC-harmonised LC-MS/MS range for men aged 19–39 (264–916 ng/dL; 9.2–31.8 nmol/L). Your own laboratory's range takes precedence over this one.
Conversion: 1 nmol/L = 28.84 ng/dL. So 1,000 ng/dL is 34.7 nmol/L — above the top of that reference range, not in the middle of it.
Free tool
Australian and New Zealand laboratories report testosterone in nmol/L. Almost everything written about it online is in ng/dL, which is why so much of what you read does not seem to match your own result. Convert between them, and see where the number actually sits.
Converted in your browser. Nothing is sent anywhere or stored.
This tool performs a unit conversion and plots the result against a published reference range. It is not a diagnosis and it cannot tell you whether your level is normal for you. Reference ranges differ between laboratories — read the range printed on your own report, and take anything that concerns you to your doctor.
How Kelo works
Every other operator in this category leads with a man, a jawline and a transformation photo. We took the personality out on purpose, because it is the thing that stops people checking the work — and the work is the only part that should matter to you.
This category runs on charisma. A man with a good jawline, a before-and-after photo and enough certainty in his voice can sell almost anything to someone who is tired, worried and has been told by a GP that everything looks normal.
In February 2026 a University of Sydney team analysed 46 high-reach testosterone posts on Instagram and TikTok, reaching 6.8 million followers between them. Not one cited any scientific evidence. Seventy-two per cent had something to sell, and two thirds linked straight to a purchase. The researchers described it as marketing and fearmongering dressed up as medical advice.
Putting a personality at the centre of this is what makes that possible. It gives you a shortcut — you decide whether you like the man, and the liking does the work that checking should have done. So we removed the shortcut. There is nobody here to like.
What is left is the part that should have been load-bearing all along: a published panel specification, a cited evidence page that includes the findings that went against us, a list of the people we refuse to sell to, a safety page with real numbers on it, and two free tools that work whether or not you ever buy anything. Read those, then decide.
It is a harder way to build this business. It is slower, it converts worse in the first month, and it gives up the single most effective asset in the category. We think it is the right trade, and if you disagree there are at least a dozen operators who will happily show you their abs.
You will work with one coach, the same one throughout, and you will know exactly who they are and what they have done before you pay anything — it is covered on the first call. What we do not do is put a face on billboards and ask you to trust it. The privacy runs outward, towards the audience, never towards the person handing us money.
We trade under a brand rather than a personal name, but the business behind it is registered, contactable and accountable. If you ever need to raise something formally, the details above are what you need.
Read before you start anything
This page is a reference, not a formality. Supplements are not automatically safe because they are sold without a prescription, and pelvic floor training is one of the few exercises where doing more can genuinely make you worse. Read the sections that apply to you, and tell your doctor and pharmacist everything you take.
In Australia call 000. In New Zealand call 111. For mental health support: Lifeline 13 11 14 in Australia, or call or text 1737 in New Zealand. Do not wait to hear back from us first.
Upper levels below are for adult men and are taken from the Australian and New Zealand Nutrient Reference Values where one exists. They are ceilings, not targets. More is not better with any of these, and several are actively harmful above the line.
Only worth taking if your 25-OH vitamin D is actually low. Trials in men who were already replete found no testosterone benefit at all. Sustained high doses can raise blood calcium, which causes nausea, constipation, confusion and kidney stones.
Corrects a deficiency; it does not push a normal level higher. Long-term intake above the ceiling causes copper deficiency, which shows up as anaemia and, if it goes on, nerve damage. Take it with food — on an empty stomach it commonly causes nausea.
The ceiling applies to supplements only, not magnesium from food. The usual first sign of too much is loose stools. Glycinate is better tolerated than oxide, which is poorly absorbed and mostly produces the laxative effect.
Never supplement iron blind. Iron overload is itself a cause of low testosterone, so taking it without testing can cause the exact problem you are trying to fix. It needs a ferritin result and ideally full iron studies first.
The best-evidenced herbal here, and the one with the most real safety signal. There are published case reports of liver injury. It can also raise thyroid hormone levels and has immune-stimulating effects, which matters if you have an autoimmune condition.
Reasonable trial evidence, but limited long-term safety data. Heavy-metal contamination has been found in some products on the market, so the source genuinely matters more than the dose. Buy only from a supplier who publishes batch testing.
Usually taken at 6–10 mg to lower SHBG and nudge free testosterone up. The evidence is thin but the safety margin at these doses is wide. There is no reason to go near the ceiling.
Not a testosterone booster, and we do not sell it as one. It is the best-evidenced performance supplement there is, and it is included for outcomes rather than hormones. Safe in healthy people; take care with reduced kidney function.
We do not sell biotin, but it is in most hair, skin and nail supplements, and people forget they are taking it. It interferes with a wide range of laboratory immunoassays, producing results that are simply wrong — including a falsely normal troponin, the test used to diagnose a heart attack.
Tell your GP and your pharmacist every supplement you take, including ones you consider trivial. Pharmacists are free to talk to, they are very good at this specific question, and you do not need an appointment.
If you are on opioid painkillers long term, raise it specifically. They are one of the strongest known suppressors of testosterone, it is well recognised, and it is manageable — but never stop or reduce prescribed medication on your own.
An over-tight pelvic floor causes its own set of problems, and they look almost identical to the problems people start training to fix. This is why kegels picked up off the internet so often make things worse: the person needed to learn to relax those muscles, and spent three months tightening them instead.
A badly timed or badly prepared blood test is worse than no test, because you will make decisions on it.
If you have a reaction to anything, report it. Reporting is how patterns get spotted, and it is genuinely useful even when you are not certain the supplement caused it.
Report adverse events to the Therapeutic Goods Administration. You can report as a consumer, without going through a doctor.
Report to the Centre for Adverse Reactions Monitoring (CARM). Consumer reports are accepted directly.
Tell us as well, at the contact address below. We keep a register of every reported reaction, and it is reviewed as part of our clinical audit.
This page is general information for adult men, not advice about your particular situation. It cannot cover every interaction, every medical condition, or every medicine. It does not replace your doctor or your pharmacist, and where this page and your own clinician disagree, follow your clinician.
Before you buy anything
Most companies in this category will take anyone's money. We would rather tell you now, because a customer we cannot help is a refund, a bad outcome, and occasionally someone who needed a doctor and spoke to a supplement company instead.
Your hormones are still running to their own schedule, and almost nothing written for men in their thirties applies to you. Most of what you will read online about optimising testosterone at your age is written by people selling to men twice it.
Go here instead: Your GP, if something genuinely feels wrong.
We do not prescribe or adjust hormone therapy, deliberately. That means we would be offering a second opinion without any of your history, on treatment we are not managing. That is not a useful thing for you to buy.
Go here instead: The prescriber who already knows your case.
We do not do that, and it is not an oversight. Keeping prescribing out of scope is exactly what lets us be straight with you about what the evidence supports, because we do not make more money when the answer is a drug.
Go here instead: A GP with an interest in men's health, or an endocrinologist.
That pattern points to the testes rather than to your lifestyle. Sleep, training, body composition and supplementation will not fix it, and we are not going to sell you a programme while pretending otherwise.
Go here instead: An endocrinologist or urologist. Ask for a referral.
We will not give you one. For reference, 1,000 ng/dL is 34.7 nmol/L — above the top of the standard adult male reference range, not in the middle of it. Anyone promising you a specific figure in advance is either guessing or lying, and both should worry you.
Go here instead: Nowhere. Be sceptical of whoever offered it.
That needs examining in person, and soon. No online service can do it, ours included, and time spent researching it is time wasted.
Go here instead: Your GP today, not next week.
Low mood and low testosterone look nearly identical from the inside — flat, tired, no drive, no interest. Untangling which is which deserves proper attention, and starting with a supplement can cost you months.
Go here instead: Your GP. It is a common overlap and a treatable one.
Then we would be guessing, and so would you. Two men with identical symptoms can have completely different panels, and the causes worth finding are only visible on one. The measurement is not a formality here, it is the product.
Go here instead: Come back when you are ready to test.
Tribulus has repeatedly failed to raise testosterone in human trials. D-aspartic acid looked promising in one early study and then did not replicate — at higher doses it has been shown to lower testosterone. We do not stock either, and we are not going to start.
Go here instead: Plenty of shops will happily sell you both.
The hormone lever runs 8 to 16 weeks and needs a retest to confirm anything actually moved. If that sounds slow, it is because it is real. The things that work quickly in this category are the things that are not true.
Go here instead: Nothing we can offer you, honestly.
Then the assessment is the right next step. It takes about three minutes, it costs nothing, and at the end of it you will know which of your habits is most likely working against you — whether or not you ever buy anything from us.
Take the assessmentIf you are in immediate distress: in Australia, Lifeline on 13 11 14. In New Zealand, call or text 1737. Both are free and available at any hour.