Not every low-T symptom is testosterone

The first week of serious men's health work in any clinic teaches a lesson that online testosterone marketing rarely acknowledges: most men who come in convinced they have "low T" do not. They have something else that produces a similar symptom set, and treating the testosterone leaves the real problem untreated. This article walks through the commonest competing diagnoses and how we work them up alongside the testosterone question.

The common symptom overlap

The symptoms that drive men to book testosterone assessment are usually some combination of fatigue, low libido, poor concentration, low mood, weight gain around the middle, reduced gym performance, sleep disturbance, and irritability. Almost all of these map to low testosterone in commercial marketing. They also map to at least six other conditions, most of which are more common than late-onset hypogonadism in the relevant age group.

Untreated sleep apnoea

If you snore, your partner has seen you stop breathing, you wake unrefreshed, and your daytime sleepiness is significant, you may have obstructive sleep apnoea. Apnoea fragments sleep dramatically (even when you feel you slept through), lowers testosterone, raises blood pressure, increases insulin resistance, and produces a symptom set indistinguishable from hypogonadism on superficial assessment.

Treating apnoea with CPAP can raise testosterone by 10 to 30 percent without any other intervention and resolves most of the symptoms at the same time. Starting TRT in a man with untreated apnoea often makes the apnoea worse (testosterone can worsen upper airway collapse) and does not address the root cause.

We screen every andropause assessment for apnoea risk and recommend a sleep study before starting TRT if risk is present.

Significant obesity

Visceral adiposity lowers testosterone through multiple mechanisms: increased aromatisation of testosterone into oestradiol in fat tissue, raised SHBG, increased inflammation, and reduced pituitary LH drive. Men in the BMI 30 to 40 range with borderline low testosterone frequently normalise simply by losing 10 to 15 kg. The effect size is clinically meaningful: studies consistently show testosterone rises of 3 to 5 nmol/L with a 15 percent weight loss.

We do not refuse to prescribe TRT to patients with obesity. We do insist that the weight question is part of the conversation, and where weight is contributing, we integrate it with the treatment plan rather than ignoring it. For some men, structured weight management (with or without GLP-1 medication) is the right first step.

Chronic opioid use

Long-term opioid use (for chronic pain, for post-surgical use that never stopped, or for recreational use) reliably suppresses LH and produces secondary hypogonadism. Modified-release codeine, morphine, tramadol, and synthetic opioids all do this. Transdermal fentanyl is particularly potent.

If you are on regular opioids and your testosterone is low, the first clinical priority is a conversation about the opioid. In some cases a supervised reduction or switch is the right answer. Where opioids remain clinically essential, TRT is appropriate as a long-term replacement.

Subclinical or overt depression

Depression suppresses libido, produces fatigue, impairs concentration, disturbs sleep, and produces low mood. Depressed men often feel they have "low T" because the symptom overlap is almost total. Standardised mood assessment (PHQ-9) at baseline catches many of these men. Treating depression with appropriate therapy, medication, or both addresses the real problem.

Men with genuinely low testosterone do sometimes have low mood as a feature of hypogonadism, and TRT can improve mood. This is a different clinical picture from primary depression with normal testosterone. Careful history and baseline bloods distinguish them.

Iron deficiency, thyroid dysfunction, B12 deficiency

Unexpected but common. Iron deficiency (even without anaemia) causes fatigue, breathlessness on exertion, and poor concentration. Hypothyroidism causes fatigue, weight gain, low mood, and reduced libido. B12 deficiency causes fatigue and cognitive dulling. All three are screened routinely in our blood panel and all three have simple treatments.

Missing hypothyroidism and diagnosing low T is a classic clinical error. The treatment for hypothyroidism (levothyroxine) costs about £20 per year. The treatment for low T costs about £1,500 per year and is lifelong. Checking TSH is a five-pound blood test.

Poor sleep from any cause

Even without formal apnoea, chronic sleep curtailment (under six hours most nights), shift work, or chronic insomnia lowers testosterone and produces hypogonadal-feeling days. Two weeks of consistent seven-to-eight hour sleep often restores testosterone meaningfully, particularly in younger men. This is free and underused.

Alcohol and recreational substance use

Heavy alcohol intake (over 21 units per week) suppresses testosterone and produces fatigue, low mood, and sexual dysfunction. Stimulants (cocaine, amphetamines) disrupt sleep and mood and often coexist with the symptoms presenting as "low T". Cannabis in heavy use has modest endocrine effects and significant effects on motivation and mood. Honest history here changes the treatment plan.

Overtraining and inadequate calorie intake

Competitive athletes, people on aggressive weight-loss diets, and men training hard with insufficient calories develop functional hypogonadism driven by energy deficit. Testosterone normalises with appropriate calorie intake and training load. We occasionally see men here who were about to be started on TRT for what was straightforward overtraining syndrome.

How we work this up

First consultation covers symptom pattern, sleep, mood screen, alcohol, medication history, weight trajectory, training volume, and relationship context. Baseline bloods include the full hormone panel, plus TSH, iron studies, B12, folate, HbA1c, lipids, and liver function. A STOP-BANG sleep apnoea screen goes with this. If risk is flagged we arrange a WatchPAT home sleep study before any TRT decision.

The honest bottom line

A good men's health assessment does not rush to TRT. It asks what else could be going on, tests for it, and treats the right thing. Sometimes the answer is testosterone. Often it is sleep, weight, alcohol, thyroid, mood, or something we have not listed. Treating the real problem is cheaper, more effective, and less lifelong than defaulting to hormones.

Ready to start?

If this article has made you think an assessment might help, the next step is a short consultation with one of our men's health doctors.

Begin your consultation at this link. Online or in person at Westfield London.