What actually affects your hormones
Learn · Hormones · Explainer, Typed Supps
Sleep, bodyweight, training and drinking affect your hormones much more than supplements do.
Stage by stage
- Sleep (The largest single lever): Five hours a night for one week lowered testosterone 10–15% in young men. No supplement matches that.
- Body fat (Aromatisation): Fat tissue converts testosterone to oestrogen, so high body fat lowers it. Very low body fat suppresses the axis instead.
- Training load (Dose-dependent): Beneficial within recovery. Sustained overload with too little food suppresses sex hormones, thyroid, and bone health.
- Alcohol & stress (Both suppress): Regular heavy drinking and chronic stress both lower testosterone. Modifiable, and larger effects than any booster.
What the evidence supports
- Sleep restriction lowers testosterone in men — moderate evidence. Demonstrated in controlled sleep-restriction studies, with a clear and reversible effect.
- High body fat is associated with lower testosterone in men — strong evidence. Consistent, with a well-characterised mechanism via aromatase.
- Low energy availability suppresses reproductive hormones in both sexes — strong evidence. The basis of the relative energy deficiency in sport framework, and well supported.
- Over-the-counter testosterone boosters raise testosterone — insufficient evidence. Stated deliberately as a negative. The best-selling ingredients have been tested and do not.
Timing
There is no dose to time here. The interventions are behavioural, and their effects are measured in weeks to months.
Time to effect
- ~1 wk: Sleep changes show in hormone measurements.
- Months: Body-fat and training-load effects accumulate.
Common myth
“A test booster will raise my testosterone.” In reality: The two most-sold ingredients have both been properly tested and found to do nothing. Sleep, body fat, alcohol and training load are where the real effect sizes are.
In the glossary
Sources