In 2015, psychologists Christina Sagioglou and Tobias Greitemeyer carried out two studies with 953 American adults to investigate the possible connection between taste preferences and personality traits. Participants assessed their enjoyment of a range of bitter, sweet, salty, and sour foods, such as black coffee and tonic water. The objective of the study was to analyze correlations between these preferences and characteristics like Machiavellianism, narcissism, everyday sadism, and psychopathy. Published in the journal Appetite, the research reported a consistent positive correlation between a preference for bitter tastes and elevated scores on these antisocial personality traits, with the strongest associations observed for sadism and psychopathy.
It is essential to comprehend what the results of the study actually reveal. The study was correlational, evaluating existing preferences and personality traits at the same time, but it did not imply a causal relationship between them. This indicates that the research did not investigate whether modifying one’s taste preference, such as changing from a sweetened beverage to unsweetened black coffee, has an effect on personality traits.
Nevertheless, the findings come with complexities, including the replication issue. In 2017, an undergraduate researcher at Rollins College, Lauren Waymire, attempted a partial replication of the original study with a limited sample of 40 participants, employing laboratory taste testing. This replication did not uncover the specific connection between bitter taste preference and psychopathy but did identify a different correlation between psychopathy scores and extraversion. Given the small sample size and research nature, this study does not negate the original findings but does suggest caution in interpretation.
A systematic review conducted in 2025 by Ziang Li and colleagues evaluated 24 studies on taste preference and personality traits, reinforcing the association between bitter and sour tastes and antisocial personality traits across multiple investigations. However, Li’s review stressed the importance of standardized measurements and diverse samples before these associations can be regarded as definitive.
Sagioglou and Greitemeyer proposed that a general tolerance for unpleasant sensations might serve as the connection between the two aspects, rather than bitterness directly influencing personality. This indicates that individuals who can tolerate unpleasant sensations, such as bitter tastes, may independently score higher on traits associated with reduced sensitivity to others’ distress, linking more to general aversion tolerance rather than a direct cause from taste to personality.
For latte drinkers, this research does not suggest that personality traits are fixed based on taste preferences. Preferences for bitterness may evolve over time due to repeated exposure. Additionally, a latte and a black coffee differ fundamentally in caffeine content and preparation, and any variation in mood or focus could be linked to changes in caffeine or sugar rather than shifts in personality.
In conclusion, the study emphasizes that a modest correlation exists between bitter taste preference and certain antisocial personality traits but does not indicate causation. The widespread belief that replacing a latte with black coffee could alter someone’s personality extends the findings of the study beyond their intended scope. This research highlights potential connections but necessitates further standardized and comprehensive investigations to delve deeper into these preliminary correlational findings.