The Study
Investigating the effects of single-dose intranasal testosterone on economic preferences in a large randomized trial of men
This study gave some men a one-time nasal spray of testosterone and others a fake spray, then watched how they made choices in games. Because it was fair and random, we can say the spray didn't change their choices — but only for this one time and only for men like the ones in the study.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Scientists gave 1,000 men either a nasal spray with testosterone or a fake one, then watched how they made decisions about money, fairness, and competition.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 590 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Even though testosterone is often blamed for bold or selfish behavior, this study shows that a single dose doesn’t make men act differently in money games.
- 2No difference between the testosterone and placebo groups — testosterone didn’t change how much they shared, risked, or competed, even though testosterone levels rose in the treatment group.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Proceedings of the National Academy of Sciences of the United States of America
Year
2025
Authors
Anna Dreber, M. Johannesson, G. Nave, Coren L Apicella, S. Geniole, Taisuke Imai, Erik L Knight, Dylan Manfredi, Pranjal Mehta, Valentina Proietti, Steven J. Stanton, Alina Zeltikova, Francesca R Luberti, Triana L. Ortiz, J. M. Carré
Related Content
Claims (5)
A single 11 mg nasal dose of testosterone does not change how healthy men aged 18–45 make decisions about risk, fairness, generosity, or competition.
In healthy men, the natural level of testosterone in saliva shows no measurable relationship with how people make decisions about risk, fairness, or competition.
Large, well-designed studies do not confirm that testosterone increases risk-taking, generosity, or competitiveness in men, suggesting earlier smaller studies produced misleading results because they were underpowered and not preregistered.
In a study of 1,000 men, giving testosterone did not change economic decision-making differently depending on a person's starting hormone levels or personality traits like dominance or impulsivity.
A single dose of testosterone given to healthy men did not change economic preferences, but this does not mean that long-term exposure, early-life exposure, or effects in women have no impact on economic preferences.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.