Andropause isn't just "low T." Five hormones are drifting in your 40s and 50s.

The panic-blogosphere has flattened male midlife endocrinology into a single number on a single lab. The real picture is five hormones moving on different curves, with different consequences.

Spend ten minutes inside the men's-health internet and you'll come away thinking male midlife is one hormone with one problem: testosterone, going down. This is wrong. Testosterone is one signal of five, and by the time most men notice symptoms the other four have already been drifting for years.

Drift one: total testosterone, slow and predictable

The Massachusetts Male Aging Study and the Baltimore Longitudinal Study both put the rate of total testosterone decline at roughly 1 to 2 percent per year after age 30 in healthy men. Travison and colleagues, working with the Boston Area Community Health survey, refined this in a 2007 paper in the Journal of Clinical Endocrinology and Metabolism. They found the population mean had drifted lower over decades independent of aging, meaning the reference range itself is contested.

By 55, the average healthy man has lost about a quarter of the testosterone he had at 30. The slope is genetic, weight-mediated, sleep-mediated, alcohol-mediated. It is slow enough that most men don't notice until the cumulative drop crosses a threshold.

Drift two: SHBG rises, faster than people think

Sex hormone-binding globulin ferries testosterone around the bloodstream. The fraction bound to SHBG is biologically inert. Only free T (about 2 percent of total) and albumin-bound T can act on tissue.

Stanworth and Jones, reviewing the data in Clinical Interventions in Aging in 2008, summarized the trajectory plainly. Total T drops 1 to 2 percent per year. SHBG rises roughly 1 percent per year. Free T falls faster than total T, and the gap widens with each decade.

This is why a man can have a "normal" total T and still be functionally hypogonadal at the tissue level. Total of 480 ng/dL, GP says he is fine, SHBG of 65, free T of 7 pg/mL. The free number is what his prostate, brain, and muscle actually see.

Drift three: DHEA, the quiet collapse

Dehydroepiandrosterone is the most abundant steroid hormone in the human body and the precursor to roughly half of male androgens. It also has the most dramatic age-related decline in this group. Peak DHEA-S occurs around age 25. By 75 the average man has lost about 80 percent of his peak. The decline is steeper between 40 and 60 than at any other point in the lifespan, and unlike testosterone, DHEA does not enjoy a tight feedback loop with the hypothalamus. The signal simply attenuates.

Trials of DHEA replacement have produced modest signals on mood and body composition, nothing dramatic. The point is that any man over 45 is looking at a steroidogenic substrate pool meaningfully smaller than at 30, and total T alone does not capture this.

Drift four: cortisol rises, and the curve flattens

The relationship between cortisol and aging is not a simple "stress hormone goes up." Mean 24-hour cortisol does rise modestly. More importantly, the diurnal curve flattens. Young men have a steep cortisol awakening response, a sharp morning spike followed by a fall to a very low nighttime nadir. Older men have a blunter morning rise and a higher nighttime floor.

Van Cauter and colleagues, in a frequently cited JAMA paper, documented this flattening across the lifespan and tied it directly to the loss of slow-wave sleep. The two reinforce each other: less deep sleep produces a flatter cortisol curve, and a flatter curve fragments deep sleep further.

Elevated evening cortisol suppresses overnight GH pulses, drives visceral adiposity, and interferes with Leydig cell function. It is the reason "I'm sleeping but not recovering" becomes a midlife refrain.

Drift five: growth hormone, the steepest curve

Somatopause is the technical term for the age-related decline in growth hormone secretion, and it is the steepest endocrine drop of midlife. Pulsatile GH release falls by roughly 14 percent per decade after the third decade. By 60 the typical man secretes about half the GH of his 30-year-old self. The pulses are smaller, less frequent, and clustered around the shortened periods of deep sleep he is now getting.

This is why body composition changes in midlife men do not match the calorie math. Same intake, same activity, and yet visceral fat accumulates and lean mass slips. The endocrine envelope inside which the food is being processed is different.

EMAS and what "late-onset hypogonadism" means

The clinical question is when this constellation rises to a diagnosis. The European Male Aging Study, published by Wu and colleagues in the New England Journal of Medicine in 2010, attempted to define late-onset hypogonadism rigorously across 3,369 men aged 40 to 79.

Their conclusion: a meaningful diagnosis requires three sexual symptoms (reduced morning erections, reduced libido, erectile dysfunction) plus total T below 11 nmol/L (about 317 ng/dL) plus free T below 220 pmol/L. Only about 2 percent of the cohort met all criteria, but the syndrome existed on a continuum, not as a binary.

EMAS is the antidote to both the blogosphere panic and the dismissive GP shrug. The real picture is gradient, not switch.

The clinical picture

A man in his late 40s who is paying attention notices these roughly in order. Sleep changes first. Recovery from training takes longer. Morning erections become less reliable. Mood shifts toward irritability rather than sadness. Visceral adiposity creeps up despite stable behavior. Libido drops, often last in men operating on momentum.

None of these alone is diagnostic. The pattern is what matters, and the pattern isn't "testosterone is low." The entire endocrine envelope has narrowed: less free T, less DHEA, less GH, more SHBG, more cortisol.

The bottom line

Andropause is real. It is poorly described by either the "male menopause" drama or the dismissive "it's just aging" shrug. The honest description is a coordinated drift in at least five hormones, on five different timescales, with the syndrome emerging from the pattern.

If you are in your 40s or 50s and something feels different, you are not imagining it, and not necessarily a candidate for TRT. You are a candidate for proper bloodwork read by someone who understands the system, and for the boring high-leverage moves (sleep, strength training, alcohol, body composition) that move the envelope back toward where it was a decade ago. The drugs are downstream of the biology.