Search “how to increase testosterone” and you will meet an entire industry before you meet a fact. The pattern is consistent: a symptom list broad enough that every man over 35 recognises himself in it, a mechanism explained with just enough biology to sound earned, and a product at the end.
The irritating thing is that the underlying subject is real. Testosterone does matter, it does fall with age, and a meaningful number of men do have levels low enough to be causing the symptoms they are worried about. What follows is the version without the product at the end — what testosterone does, what genuinely moves it, what supplements can and cannot do, and the point at which guessing should stop.
What testosterone actually does in the body
Most men encounter testosterone as a sex hormone and stop there. It is also a metabolic and structural one, which is why the symptoms of a low level are so scattered and so easy to attribute to something else.
Drives muscle protein synthesis. Low levels make lean mass harder to build and easier to lose.
Maintains bone mineral density. Long-standing low testosterone is a genuine fracture risk factor.
Influences where fat is stored. Low testosterone and central fat gain feed each other in both directions.
Stimulates red cell production. Unexplained mild anaemia is occasionally the first clue.
The clearest single effect. Sexual desire tracks testosterone more closely than any other symptom.
Contributes to drive and motivation — real, but smaller and less specific than commonly claimed.
The bidirectional relationship with body fat is the one worth understanding, because it explains why so many men feel they are on a slope they cannot get off. Adipose tissue contains aromatase, the enzyme that converts testosterone to oestradiol. More fat means more conversion, which means less testosterone, which makes fat easier to gain and muscle harder to hold, which means more fat. It is a loop, and it is also the reason weight loss is one of the few interventions that reliably moves the number.
What low testosterone does to sexual function
This is where the effect is least ambiguous. Libido — wanting sex at all — is the symptom most tightly linked to testosterone, and it is usually the first thing men notice, though rarely the first thing they mention.
Erectile function is more complicated, and the distinction matters because it changes what will help. An erection is primarily a vascular event: it depends on blood flow and on the endothelium lining the small penile arteries. Testosterone supports that system but does not run it. So a man with genuinely low testosterone and poor erections often has both a hormonal problem and a vascular one, and treating only the hormone leaves half the problem in place.
If desire is intact but erections are unreliable, testosterone is unlikely to be the main story and the vascular side deserves attention first. If desire itself has faded — you are not thinking about sex, not just struggling with it — that pattern points more directly at hormones and is worth testing. Our three-minute self-check separates the two, and it is free and anonymous.
Energy, focus and work: the part the internet gets wrong
The commercial version of this section writes itself: raise your testosterone, sharpen your focus, out-perform your colleagues. It is a good story. It is not what the trials found.
What is true: low testosterone causes fatigue, low motivation and depressed mood, and those unquestionably affect work. A man who is exhausted by 2pm and cannot summon interest in anything is not performing at his best, and if a hormone is behind that, correcting it helps.
What is not true is the step the marketing takes next. In the Testosterone Trials — a coordinated set of placebo-controlled trials in men aged 65 and over with low levels — raising testosterone for a year produced a moderate benefit to sexual function, some benefit to mood and depressive symptoms, and no benefit to vitality.4 The cognitive arm, run in men with age-associated memory impairment, found no improvement in verbal memory, visual memory, executive function or spatial ability.5
The practical reading: if fatigue and flatness are what brought you here, they are worth investigating — and testosterone is one of several things worth ruling in or out, alongside iron, thyroid, sleep quality and mood itself. But if you are functioning normally and hoping to move from good to exceptional, the hormone is not the lever. That is worth knowing before you spend money on it.
What actually moves testosterone
Three levers with real evidence behind them, and one thing that is not a lever at all but matters more than any of them.
1. Sleep — the largest and the most reversible
Testosterone is released mostly during sleep, and it is sensitive to losing it. In a controlled study, restricting healthy young men to under five hours a night for one week lowered daytime testosterone by 10 to 15 per cent, with the largest drop in the afternoon and evening.1 For scale, testosterone falls by roughly 1–2% a year with normal ageing.
Two honest caveats. That study had ten participants — it is a tightly controlled experiment rather than a large one, and it should be read as a demonstration that sleep matters, not as a precise number. And it did not test whether the effect reverses when the sleep comes back, so the durability is not established. It remains the most striking single finding in this article, and the intervention costs nothing.
2. Body fat — the most durable lever
Weight loss raises testosterone in men carrying excess, and the relationship scales with how much comes off. In a meta-analysis of men with obesity, a low-calorie diet raised total testosterone by around 2.9 nmol/L and bariatric surgery by around 8.7 nmol/L.2 Younger men and those starting heavier tended to gain the most.
This is slower than sleep and harder to sustain, but it addresses the aromatase loop described above rather than working around it.
3. Training — do it, and be precise about why
Exercise belongs in any sensible plan, but the popular version overstates one part and misses another. A meta-analysis of short-term training in older men found that resistance training alone did not raise resting testosterone; in the same analysis, aerobic and interval training produced small but statistically significant increases.3 The acute spike after a heavy session is real, short-lived, and not the same thing as a higher baseline.
The larger effects are indirect and still worth having: training changes body composition, improves sleep and improves insulin sensitivity, all of which sit upstream of testosterone. Over-training with poor recovery and inadequate eating pushes it the other way.
Alcohol, and the condition nobody has looked for yet
Heavy sustained alcohol intake suppresses testosterone through several routes at once. This is dose-related rather than all-or-nothing: for most men the useful conversation is about the four-nights-a-week habit, not abstinence.
More important, and not a lever at all: something may be suppressing it that nobody has looked for. Obstructive sleep apnoea is the classic one — common in men with central weight gain, and routinely undiagnosed. Poorly controlled type 2 diabetes, thyroid disease and long-term opioid use all lower testosterone. So do some prescription medicines.
If you think something you have been prescribed may be affecting your testosterone, that is a conversation to have with whoever prescribed it. Some of these medicines are doing a more important job than the side effect they cause, and stopping one without advice can be considerably more dangerous than a low hormone level.
This is also the strongest single argument for testing rather than supplementing: a capsule bought for tiredness cannot find the sleep apnoea that is causing the tiredness.
Supplements: what the evidence actually supports
This deserves a direct answer, because the category is built on the absence of one.
| Ingredient | What the trials actually found | Verdict |
|---|---|---|
| Vitamin D | Observational studies link low vitamin D to low testosterone. But randomised trials — including one run specifically in men who had both low testosterone and low vitamin D — found no effect on testosterone.6,7 | Correct a deficiency for its own sake. Do not expect testosterone to move |
| Zinc | Human evidence comes largely from disease states involving severe deficiency, not from otherwise-healthy men | Thin. Correct a measured deficiency, expect nothing beyond that |
| Ashwagandha | A 15% rise at 600 mg/day over 8 weeks in men aged 18–50 beginning resistance training — a single manufacturer-funded trial.8 See the liver warning below | The least weak herbal evidence, which is not the same as good evidence |
| Fenugreek, D-aspartic acid | Inconsistent. Some small positive trials, others null | Not established |
| Tribulus, most “blends” | No convincing evidence of raising testosterone in humans | No |
Read the middle column rather than the marketing. The strongest entry in the table is one manufacturer-funded trial, in men who were simultaneously starting a training programme, reporting a change measured in percent rather than in symptoms. No supplement in this table has been shown to treat low testosterone, and none is claimed to here.
Adulteration. Regulators have repeatedly found products sold as testosterone boosters, male enhancement or body-building supplements to contain undeclared anabolic steroids and SARMs. A review of reports to the US FDA identified 35 men aged 20 to 48 with serious liver injury linked to body-building products, some requiring hospitalisation.9,10
Ashwagandha itself. The ingredient with the best data in the table above is also a recognised cause of liver injury — the US National Institutes of Health LiverTox database rates it a probable cause of clinically apparent liver injury, typically appearing between two and twelve weeks of starting it, usually with jaundice, and in rare cases severe.14 It can also interact with thyroid medication and with sedatives. That does not make it unusable; it makes it something to take knowingly and to mention to your doctor.
If you are taking anything and develop yellowing of the eyes or skin, dark urine, or persistent pain under the right ribs, stop it and see a doctor.
So is there any sensible role for a supplement?
A narrow one, and it is worth being exact about its edges:
- Correcting a measured deficiency is worth doing on its own merits. If your vitamin D is low, correcting it is good for your bones and worth doing. Just do not expect your testosterone to follow — the trials say it does not.
- Supporting what is genuinely upstream. Sleep and stress are the two biggest modifiable inputs in this article. Something that measurably helps you sleep is acting on the largest lever here, even if it never touches a hormone.
What there is not is a supplement that treats low testosterone. If your level is genuinely low, the thing that changes it is finding out why.
It is tempting to treat Philippine FDA registration as the answer to the adulteration problem above. It is not. Registration is a product notification process — it does not batch-test for undeclared steroids, verify that the stated dose is in the capsule, or assess whether the product works. It is a floor worth insisting on, not a guarantee. Prefer named ingredients at stated doses over a proprietary blend, be sceptical of anything sold with steroid-adjacent language or before-and-after physiques, and tell your doctor what you are taking.
When to stop guessing and test
Everything above is worth doing on its own merits. None of it tells you whether your testosterone is actually low, and most men who suspect it turn out to have normal levels — which is genuinely useful to know, because it redirects the search to what is causing the symptoms.
How it is properly done: testosterone follows a daily rhythm, peaking in the morning, so one reading is not enough to act on. The standard is two separate early-morning fasting samples, typically before 10–11am, with a commonly used threshold around 300 ng/dL for total testosterone. A diagnosis needs both a low level on two occasions and symptoms that fit.
Two things worth knowing before you interpret a number yourself. Testosterone assays vary, and a single borderline result is not a diagnosis — the Endocrine Society noted in 2026 that testing is often inaccurate and that diagnosis should rest on consistently low, accurately measured levels.11 And total testosterone is not the whole picture: free testosterone is sometimes the more informative measure, particularly in men with obesity or diabetes, where the binding protein is altered. This is why the result needs interpreting alongside the symptoms rather than read off a reference range.
If levels are genuinely low and symptomatic, testosterone replacement is a real option and a serious one. The largest cardiovascular safety trial to date found it non-inferior to placebo for major cardiac events in men at elevated risk — but recorded more pulmonary embolism, more atrial fibrillation and more acute kidney injury in the treated group,12 and a fracture substudy of the same trial found more fractures, not fewer.13 Ongoing monitoring is not optional: red cell count can rise to a degree that requires stopping, the prostate needs watching, sleep apnoea can worsen, and effects on fertility may not fully reverse. It is a decision to make slowly with a clinician, and a poor reason to skip the lifestyle work — the two are not alternatives.
Our companion article on low testosterone in Filipino men covers the symptom picture and the testing pathway in more detail.
Where we fit
We are a small, discreet, nurse-led clinic in Makati, and our role on this subject is narrow enough to be worth stating plainly. We arrange the morning blood test through accredited laboratory partners and go through the result with you privately — what it means, what it does not, and what a sensible next step looks like, whether that is the lifestyle work above, investigating something underlying, or referral onward.
We do not initiate or manage testosterone replacement. That belongs with a specialist, and we will say so rather than sell you something adjacent. One patient at a time, no waiting room, no name on the door.