The honest answer: for most men, the biggest lever is lifestyle, not a supplement. Losing excess body fat, training, sleeping well, keeping stress in check and eating properly do far more for your testosterone than any pill in a tub. In a recent Healthcast episode, endocrinologist Diederik Smit and clinical pharmacologist Tijs Verdegaal walk through how testosterone really works, how to measure it properly, and when medical treatment is actually worth considering. This is general information, not a substitute for medical advice. If you are worried about your levels or symptoms, speak to a doctor.
What counts as a normal testosterone level?
Start with the measurement, because that is where a lot goes wrong. Testosterone is measured from blood, in the morning, fasted, ideally before 9am. Later in the day and after eating, the reading drops. Verdegaal compares a test taken at a random time to sticking a thermometer out of the window without knowing the season: 10 degrees can feel warm in winter and cold in summer.
And what actually counts as low? Often less than people assume. Reference ranges come from population studies, and the average for a healthy man without excess weight sits somewhere around 15. A reading of 14 is already close to average, not a crisis. It is also worth asking for your free testosterone and SHBG, because the total figure on its own does not tell the full story.
Why does testosterone drop?
The decline that comes with age is largely down to lifestyle, not ageing on its own. The two biggest drivers are becoming less healthy in general (chronic conditions creeping in) and carrying more body fat. Fat tissue converts testosterone into oestradiol, which in turn dampens your own production. A genuinely healthy man in his sixties or seventies often still holds perfectly good levels.
How dramatically lifestyle can hit the numbers shows up in research on heavily strained soldiers: through sleep deprivation and stress, their testosterone fell on average from around 17 to about 2.5. That is not typical daily life, but it makes the point that the body responds fast to how you treat it.
How to support your testosterone naturally
These are the levers you can actually pull yourself:
- Lose excess body fat if you are carrying it. This is one of the strongest levers of all.
- Train, both strength and cardio.
- Sleep well and enough.
- Keep chronic stress in check.
- Eat a balanced diet with enough calories, protein and micronutrients.
Vitamin D, zinc and magnesium get mentioned a lot, but they mainly help if you are actually deficient. A varied diet usually covers that already. As Smit puts it: sleeping well, training well and eating well does far more for your testosterone than any random supplement.
Do testosterone boosters work?
Supplements like tongkat ali, ashwagandha, shilajit, fenugreek and tribulus have modest evidence and, at best, a small effect. Most of the time they do little harm, but do not expect miracles. In the UK a month’s supply of one of these typically runs into the tens of pounds, and the return on that spend is usually far smaller than a few weeks of better sleep and training. The gains sit in your lifestyle, not in a tub.
When is medical treatment (TRT) actually worth it?
Only when you have a repeatedly measured, consistently low level together with matching symptoms, and after other causes have been ruled out. One low reading after a bad night means nothing. Both doctors are firm on this.
Sourcing testosterone yourself from the black market is genuinely risky. It can strain your heart and blood vessels over the long term and can permanently damage your own production. Verdegaal calls it very short-term thinking. If you want to go down this route, do it through a doctor, not on your own.
Frequently asked questions
How do you measure testosterone reliably?
From blood, in the morning and fasted, ideally before 9am. Alongside total testosterone, ask for your free testosterone and SHBG so you get a complete picture rather than just one number.
My level is 14, is that low?
Usually not. The average for a healthy man sits around 15, so 14 is close to average. And one reading tells you little on its own, so if in doubt, measure again on another morning.
How do I raise my testosterone naturally?
Lose any excess body fat, train (both strength and cardio), sleep enough, keep stress in check and eat a balanced diet. These are by far the strongest factors.
Do vitamin D, zinc and magnesium help?
Mainly if you are actually deficient. On a varied diet they usually add little to your testosterone, so a general top-up is not a magic fix.
Do testosterone boosters work?
The evidence is modest and the effect small. They are usually harmless, but do not expect much. Lifestyle does far more than any booster.
When is testosterone therapy (TRT) worth considering?
Only with a repeatedly low level plus matching symptoms, once other causes have been ruled out. Starting it yourself from the black market is risky, so always go through a doctor.
