Do Testosterone Supplements Affect Moral Judgment?

It may seem rather far-fetched to say that testosterone supplements affect moral judgment or reasoning. After all, these supplements are usually prescribed to help relieve symptoms of hypogonadism (excessively low testosterone), as well as used off-label by men who are worried about low testosterone.

Yet that’s what the results of some studies are suggesting. More specifically, the authors of a new study at the University of Texas at Austin propose that testosterone supplements can make men more sensitive to moral norms.

Testosterone and moral judgment

According to Bertram Gawronski, a psychology professor at the University of Texas at Austin, “There’s been an increasing interest in how hormones influence moral judgments in a fundamental way by regulating brain activity.” In this new study, researchers evaluated the impact of testosterone on moral judgment by presenting situations to participants after they had been given testosterone or a placebo.

In the double-blind study, testosterone was given to 100 participants and placebo was given to another 100 subjects. The participants were then presented with the following situation: a runaway trolley will kill five individuals unless someone chooses to pull a lever that will send the trolley to a different track, which will kill one person. Essentially, the situation was whether to allow five individuals to die or only one.

The authors noted that “counter to predictions, testosterone administration led to increased inaction in moral dilemmas where harmful actions prohibited by moral norms increase overall well-being.” In contrast, other analyses indicates that “higher levels of endogenous testosterone [naturally occurring testosterone] were associated with lower sensitivity to moral norms.”

The researchers suggested that a reason for the difference between moral judgment responses from exogenous (supplemental) and endogenous testosterone may be because individuals with certain personality characteristics tend to have different levels of testosterone. 

According to Gawronski, the findings of this study challenge some of the main hypotheses about how testosterone affects moral judgments. He emphasized that their results “echo the importance of distinguishing between causation and correlation in research on neuroendocrine determinants of human behavior,” since the impact of testosterone supplementation on moral judgments can be the opposite of that seen with endogenous testosterone.

Bottom line

Use of testosterone supplements may have an impact on a man’s moral judgment and reasoning that differs from that observed with naturally occurring hormone. As another point of interest, it also turns out that other research has found the same thing seems to be true for women.


Brannon SM et al. Exogenous testosterone increases sensitivity to moral norms in moral dilemma judgements. Nature Human Behavior 2019 Aug; 3(8): 856-66

Chen C et al. Testosterone administration in females modulates moral judgment and patterns of brain activation and functional connectivity. Human Brain Mapping 2016 Oct; 37(10): 3417-30

Wood J. Effects of testosterone on moral reasoning: it’s complicated. PsychCentral 2019 Aug 18