Does lion's mane increase testosterone?

The empty hormone file: what has and has not been measured, the marketing chain that produced the question, and why the mushroom's mechanism never reaches the testes

Does lion's mane increase testosterone is a question whose answer is found by opening a file, and the file is empty. No human study of lion's mane has measured testosterone, free or total, in men or women; none has measured oestrogen, cortisol, luteinising hormone, follicle-stimulating hormone, sex hormone-binding globulin or any other endocrine marker, as a primary outcome, a secondary outcome or an incidental blood test. The sixteen-week Japanese trial in older adults measured a cognitive scale; the young-adult pilot measured cognition, stress and mood scales; the menopausal cookie study measured mood and complaint questionnaires and took no blood. The animal literature, which is where most lion's mane claims originate, has not been designed to ask the question either: the rodent studies address nerve injury, cognitive decline, mood behaviour and, in a few, metabolism on high-fat diets, and none has reported testosterone as an outcome in a way that has entered the review literature. And there is no mechanism on offer: the mushroom's characterised activity is the stimulation of nerve growth factor synthesis by its hericenones and erinacines in cell culture, a signalling protein involved in neuron survival, and nothing in that story reaches the Leydig cells of the testes or the pituitary and hypothalamus that drive them. So where did the question come from? From a marketing chain built by association: nerve growth factor in a dish becomes nerve health, nerve health becomes vitality, vitality becomes energy, drive and masculinity, and masculinity becomes testosterone, with each link a word substitution and none a measurement, until a mushroom with no endocrine data appears on lists of natural testosterone boosters beside tongkat ali and fenugreek, which at least have small trials of their own to be sceptical about. The honest answer to the question as asked is therefore not that lion's mane fails to raise testosterone, which would imply someone looked, but that nobody has looked, there is no reason to expect anything, and no supplement of any kind holds a testosterone claim on the UK register, so the sentence may not be printed on any tub. A lifter who takes lion's mane and feels more driven in the weeks after is feeling the coffee it rode with, the programme they started, the sleep they fixed to take it or the expectation the list set, and the way to know is not a feeling but a morning blood test, which is where the second half of this page goes.

Five levers with numbers: sleep, body fat, energy availability, training and the two deficiency nutrients, the morning blood test, and the honest buy

If the mushroom's file is empty, a lifter asking the question deserves the files that are not, and testosterone in men has five modifiable levers with evidence and, for the first, a number worth memorising. Lever one is sleep, and the number is from a controlled study in young healthy men: one week of five-hour nights lowered daytime testosterone by 10 to 15 percent, a drop equivalent to ten to fifteen years of ageing, in seven days, in men in their twenties, and it reversed with recovery sleep. Most of testosterone's daily production happens during sleep, so the lifter running six-hour nights through a training block and researching natural boosters has the largest and most reversible lever in the whole list sitting unpulled, and no capsule compensates for it. Lever two is body fat: adipose tissue converts testosterone to oestrogen through aromatase, men with obesity have lower testosterone, and weight loss in those men raises it meaningfully; a lean lifter has little to gain from this lever, and a lifter carrying excess fat has a great deal, by diet and training rather than by anything swallowed. Lever three is energy availability, the lever lifters pull the wrong way: a prolonged hard deficit, a long cut or a contest prep, lowers testosterone as the body downregulates reproduction when fuel is short, and the levels recover when eating returns to maintenance, which is why the end of a cut feels the way it does and why a cut should have an end. Lever four is resistance training itself, which raises testosterone acutely for around an hour after a heavy compound session, an effect that has not been shown to drive muscle gain on its own, and supports it chronically through body composition, sleep and energy balance, which do. Lever five is the two nutrients, zinc and vitamin D, each of which raises testosterone in men who were deficient in it and does nothing in men who were replete, so each is a blood test and a correction rather than a supplement bought on hope; a lifter sweating heavily through a UK winter may well be short of both, and a lifter eating meat and getting sun is usually short of neither. The morning blood test is the test, because testosterone peaks in the early morning and varies through the day, and a doctor reading a morning total and free testosterone alongside the person's symptoms is the only way to know whether low testosterone is present, what is driving it and whether it needs treatment; a feeling from a capsule tells nobody anything. Lion's mane holds no authorised UK health claim of any kind, and this site describes its two small cognitive studies as studies. Bought, if at all, for those studies and not for a hormone it has never been shown to touch: a stated 5:1 fruiting body extract labelled 1500mg mushroom equivalent, 120 capsules for £15.49, 120 days at 13p, vegan shell, UK made under GMP and BRC, independently lab tested, with no testosterone sentence on its label because none is allowed and none is earned.

What to check on the label