A man arrives tired, flat, carrying weight around the middle, with a libido that has quietly disappeared. He has read about low testosterone and he is probably right that his level is low. What gets missed is why.
Medically reviewed by Kent Cohen, MD, FACEP — Medical Director, Balanced Bodies: Longevity + Wellness Clinic. Last reviewed October 2026.
Testosterone is made while you sleep
Testosterone production follows a daily rhythm, rising through the night and peaking in the early morning. Most of it is produced during sleep, and the deeper stages matter most.
Which means anything that fragments sleep interferes with production at the source. In healthy men, restricting sleep to around five hours a night for a week measurably lowers daytime testosterone. Obstructive sleep apnoea does something similar, night after night, for years.
What obstructive sleep apnoea is doing
The airway narrows or closes repeatedly during sleep. Each event drops your oxygen level and pulls you briefly toward wakefulness — often without you knowing. This can happen dozens of times an hour.
You never reach or sustain the deep sleep where most testosterone production occurs. The repeated oxygen dips and the stress response they trigger compound it.
The result is a man who sleeps eight hours and wakes unrefreshed, with a genuinely low testosterone level that has a cause nobody has looked for.
The symptom lists are nearly identical
Put them side by side and the overlap is striking. Both produce fatigue and low energy, poor concentration, low mood and irritability, reduced libido, erectile difficulty, and weight gain that resists effort.
Sleep apnoea adds a few of its own: snoring, witnessed pauses in breathing, waking with a dry mouth or headache, needing to urinate several times a night, and falling asleep easily during the day.
If any of those sound familiar, say so at your consultation. It changes what we look for.
Why the direction matters
If sleep apnoea is driving your low testosterone, treating the apnoea can raise it — sometimes substantially — without any hormone therapy at all.
Treat the testosterone instead and you may feel somewhat better while the underlying condition continues. That matters, because untreated sleep apnoea is associated with hypertension, cardiovascular disease, type 2 diabetes and stroke risk. It is a more serious diagnosis than low testosterone and it is the one worth finding.
There is a further consideration: testosterone therapy can worsen sleep apnoea in some men. Prescribing it to someone with undiagnosed apnoea is the wrong order of operations.
They often travel together
To be clear, this is not an either-or. Excess weight contributes to sleep apnoea, sleep apnoea suppresses testosterone, and low testosterone makes it harder to maintain the muscle mass that helps with weight — each feeding the next.
Some men need both addressed. The point is not that testosterone therapy is wrong; it is that starting it without asking about sleep means nobody ever finds the other half.
What we do about it
We ask. Snoring, witnessed pauses, how you feel on waking, whether you fall asleep during the day, and whether a partner has noticed anything.
If the picture suggests sleep apnoea, we will say so and recommend a sleep study. We do not diagnose or treat it — that needs a sleep physician — but identifying it is the useful part, and it is a referral worth making before starting hormone therapy rather than after.
If your labs confirm low testosterone and treatment is appropriate, that is $100 a month including monitoring. If the answer is that your sleep is the problem, you will leave with that instead, and it is the more valuable finding.
More on what else produces this picture in our guide to low testosterone symptoms.
Book a free consultation or call (678) 919-4845.
Further reading
This article is general information, not medical advice. We do not diagnose or treat sleep apnoea; suspected cases are referred for a sleep study.
