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HEALTH

The Claim

In men, testosterone secretion is highest in the morning, making male aggression highest in the morning.

Verified by Lenz ·

The Short Version

Morning testosterone peaks in many men are well documented, but the claim’s main takeaway does not follow. Evidence does not show that male aggression is highest in the morning, and baseline testosterone has only a weak, context-dependent relationship with aggression. Age and health status also affect how strong the morning hormone peak is.

Caveats

  • A time-of-day hormone pattern does not by itself establish a matching time-of-day behavior pattern; the causal jump is unsupported.
  • Research on testosterone and aggression finds only a small, inconsistent association, with social context and challenge-induced changes often mattering more than baseline levels.
  • The morning testosterone peak is not equally strong in all men; it tends to diminish with age and may be minimal in some clinical populations.

The Receipts

  1. Circadian rhythm of testosterone level in plasma. I. Physiologic 24 ...

    PubMed

  2. Measurement of testosterone: how important is a morning blood draw?

    PubMed

  3. The Effect of Diurnal Variation on Clinical Measurement of Serum Testosterone and Other Sex Hormone Levels in Men

    PMC (PubMed Central)

  4. Is testosterone linked to human aggression? A meta-analytic ...

    PubMed

  5. Testosterone and Aggressive Behavior in Man - PMC - NIH

    PMC - NIH

  6. Diurnal rhythm of testosterone

    PubMed

  7. Testosterone and Aggressive Behavior in Man

    PMC

  8. Testosterone and Human Aggression: an Evaluation of the Challenge Hypothesis

    PMC

  9. No evidence for a relationship between testosterone and aggression in humans: a meta-analysis

    PubMed

  10. Analysis of diurnal variation in serum testosterone levels in men with hypogonadism

    PubMed

+ 18 more sources — see the full list on Lenz

Filed Under

testosterone

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