Black Coffee and Personality: What the Psychopath Claim Actually Shows
Author: Ukrainian Psychological Hub · Published: September 28, 2026 · Editorial Policy
No. Drinking black coffee does not show that someone is a psychopath. The viral claim is a dramatic rewrite of a much narrower research finding: a 2016 study reported group-level associations between self-reported liking for bitter tastes and scores on several antisocial personality-trait measures. Coffee appeared among examples of bitter foods and drinks, but the researchers did not test whether black-coffee drinkers could be identified as psychopaths, and they did not diagnose people from their coffee habits. The original study involved two U.S. community samples totaling 953 adults.
The distinction matters because the internet version compresses several different ideas into one sentence. “Black coffee” is a way of serving coffee without milk, cream, sugar, or other additions. “Bitter taste preference” is a broader sensory preference that can include many foods and drinks. “Psychopathy” is a psychological construct assessed with specialized measures; it is not a label that can be assigned from a beverage order. A statistical association between two variables in a group is not an individual personality test.
Evidence status: there is peer-reviewed evidence for an association between general bitter-taste preference and psychopathy/sadism trait scores in the 2016 study, and later work by the same authors found related associations in broader research on aversive or “benignly masochistic” preferences. The evidence does not establish that black coffee causes antisocial traits, that black-coffee drinkers form a distinct personality type, or that a coffee order can diagnose psychopathy. A small laboratory replication attempt did not reproduce the original bitter-preference/psychopathy association, although that thesis was underpowered and does not settle the question by itself. Sagioglou & Greitemeyer, 2016; Sagioglou & Greitemeyer, 2020; Waymire, 2017.
For the broader psychology of caffeine, habit, ritual, expectation, taste, and social context, see The Psychology of Coffee: Mood, Attention, Habit, Ritual, Taste, and Social Life. For the beverage itself, including beans, brewing, caffeine, and sensory properties, see Coffee: Beans, Drinks, Caffeine, Brewing, Taste, and Psychology.
For the broader evidence question of what coffee preference can and cannot reveal about stable personality, see Coffee and Personality: What Your Coffee Preference Can and Cannot Say About You. For the separate question of what a café order can communicate as a habit, identity cue, or social signal, see What Does Your Coffee Order Say About You? Personality Claims vs Social Signals.
Where the “Black Coffee Drinkers Are Psychopaths” Claim Came From
The modern claim can be traced mainly to a paper by Christina Sagioglou and Tobias Greitemeyer, published in Appetite. Its actual title was “Individual differences in bitter taste preferences are associated with antisocial personality traits.” The title itself is already more precise than the meme: it says bitter taste preferences, not black coffee; associated, not caused; and personality traits, not a clinical verdict. PubMed record and abstract.
The researchers recruited two U.S. community samples through Amazon Mechanical Turk. Study 1 included 504 participants and Study 2 included 449, for a combined sample of 953 adults. Participants reported how much they liked different tastes and food or drink items, and they completed questionnaires measuring Machiavellianism, psychopathy, narcissism, everyday sadism, aggression, and Big Five personality dimensions. The project was cross-sectional: taste preferences and personality scores were measured, not experimentally created. Sagioglou & Greitemeyer, 2016.
That design can answer a limited question: do people who report stronger liking for bitterness also tend, on average, to score differently on certain personality scales? It cannot establish that bitterness produces a personality trait, that personality produces a taste preference, or that a particular drink identifies a particular kind of person.
What the 2016 Study Actually Tested
Study 1: general taste preference and food-specific preference
In Study 1, participants rated their liking for food items intended to represent sweet, sour, salty, and bitter tastes. Coffee and radishes were given as examples of bitter items. They also answered separate general questions about how much they liked bitter, sweet, sour, and salty foods and drinks. Crucially, participants did not actually taste coffee or other foods in this study. The paper states that the measures were self-reported liking of food names and taste categories. Sagioglou & Greitemeyer, 2016.
This produced two conceptually different measures. One was a general statement such as liking bitter foods and drinks. The other averaged preferences for particular foods that researchers had classified into taste categories. That distinction became important because the two measures did not behave the same way.
For the general bitter-preference measure, higher liking for bitterness was associated with higher psychopathy and everyday sadism scores and with lower agreeableness. Yet the food-specific bitter measure did not show the same pattern: in Study 1 it was significantly related to openness, not to the antisocial variables. That internal mismatch is one of the most important details lost in viral retellings. Sagioglou & Greitemeyer, 2016.
Study 2: the researchers checked whether the supposedly bitter foods were actually perceived as bitter
Study 2 repeated the general approach with 449 participants and asked people to rate the taste qualities of the food items. Only five of the ten items originally grouped as bitter were predominantly rated as bitter: coffee, beer, radishes, tonic water, and celery. Cottage cheese, ginger ale, grapefruit juice, rye bread, and tea were not predominantly experienced as bitter. The authors therefore recalculated a food-specific composite using the five items that participants actually rated mainly bitter. Sagioglou & Greitemeyer, 2016.
Even after that correction, the food-specific bitter-preference measure still did not reproduce the general-measure pattern for the Dark Tetrad. The paper reports that the food-specific composite was instead associated with extraversion and openness. By contrast, the broad question about liking bitter foods and drinks again correlated with psychopathy and everyday sadism, and in Study 2 also with Machiavellianism and narcissism. Sagioglou & Greitemeyer, 2016.
The authors themselves treated this discrepancy as a limitation. They noted that the general bitter-preference question might partly capture a stereotype or semantic idea of being “bitter,” rather than the same thing as liking concrete bitter foods. That possibility does not invalidate the entire study, but it sharply limits the move from a general survey item to a claim about a real cup of black coffee.
What the Study Found—and How Large the Signal Was
The original paper did find statistically significant relationships. In Study 1, when sweet, sour, salty, and bitter preferences were entered together, the model explained about 2.4% of the variance in psychopathy scores and 3.2% of the variance in everyday sadism. The standardized coefficient for bitter preference was about .11 for psychopathy and .12 for everyday sadism. Those numbers show a detectable group-level signal in that sample, while also showing how little of an individual’s score was explained by taste preferences. Sagioglou & Greitemeyer, 2016.
Study 2 produced somewhat stronger associations for the general bitter-preference measure: the four-taste models explained about 4.2% of variance in psychopathy and 6.4% in everyday sadism, with bitter preference again a significant predictor. These are research associations, not classification rules. A variable can be statistically significant in a large sample and still be far too weak and context-dependent to identify a person. Sagioglou & Greitemeyer, 2016.
This is the point at which a headline can become misleading. “Bitter preference was associated with higher psychopathy-trait scores” is a defensible summary of one measure in the study. “Black coffee drinkers are psychopaths” changes the exposure, changes the outcome, and changes a group correlation into an individual label.
Why the Viral “Psychopath” Headline Overstates the Evidence
The first exaggeration is sensory. Black coffee and general bitterness are not interchangeable. Coffee is one item inside a complex class of bitter foods and drinks, and black coffee itself varies enormously in bitterness depending on bean chemistry, roast, grind, water, extraction, concentration, temperature, and brewing method. Coffee bitterness arises from multiple compounds acting on multiple bitter receptors; caffeine contributes, but it is not the sole source. Lang et al., 2020.
The second exaggeration is psychological. The study measured psychopathy as a dimensional personality-trait score in a community sample. It did not conduct clinical or forensic evaluations and did not sort participants into “psychopath” and “non-psychopath” groups based on coffee. Psychopathy and antisocial personality disorder are related but distinct constructs in contemporary personality research; neither can be inferred from an everyday preference. Anderson & Kelley, 2022.
The third exaggeration is statistical. Correlation describes covariation across observations. It does not mean that the relationship is strong enough for individual prediction, and it does not establish a causal direction. People can arrive at the same beverage preference through very different biological, sensory, learned, social, practical, and cultural pathways.
The fourth exaggeration is categorical. A person who enjoys one black coffee is not thereby expressing a stable “black-coffee personality.” Preferences change by bean, roast, recipe, time of day, context, caffeine state, health goals, social setting, and experience. A person can enjoy black filter coffee, dislike straight espresso, sweeten a dark roast, and prefer milk in another drink without changing personality each time.
Black Coffee Is Not a Fixed Measure of Bitterness
Black coffee simply means coffee served without additions that substantially change the drink, especially milk or cream and sweeteners. It does not specify species, roast level, brew method, extraction, concentration, origin, processing, or sensory balance. Two black coffees can differ more from each other in bitterness than one black coffee differs from a coffee with a small amount of milk.
One further correction is easy to miss: the original food list used “coffee” as an item; it did not define a category of people who drink coffee black. In Study 2, the authors explicitly noted that sugar and milk can mask coffee’s bitterness and used that as one reason to question whether named foods cleanly represent taste categories. Turning “coffee” into “black coffee” therefore adds a condition that the study itself did not test as a personality marker. Sagioglou & Greitemeyer, 2016.
Controlled sensory work shows that roast level, total dissolved solids, and extraction yield can change bitterness, sourness, sweetness, body, and other attributes of drip coffee. In other words, “black” tells you what has not been added; it does not tell you how bitter the beverage objectively or subjectively is. Frost, Ristenpart, & Guinard, 2020.
Coffee also contains several families of bitter compounds, and human bitter perception depends on interactions between chemistry and receptor biology. Caffeine is bitter, yet coffee bitterness cannot be reduced to caffeine concentration. Lang et al., 2020 For a full coffee-domain explanation, see Why Does Coffee Taste Bitter? Chemistry, Brewing, and the Psychology of Bitterness.
This matters for personality research because a person choosing “black coffee” is not selecting a standardized bitter stimulus. The sensory input differs from cup to cup, while preference is shaped by the drinker’s perceptual sensitivity and experience.
Why People Like Black Coffee
Taste sensitivity differs between people
People differ in how strongly they perceive bitter compounds. Bitter-taste receptor genetics contributes to some of that variation, but genetics only partially predicts what people ultimately like, choose, and consume. Reviews of bitter-taste genetics emphasize that preference emerges from a more complicated interaction of sensory phenotype, learning, exposure, context, and other biological factors. Beckett et al., 2014.
Coffee-specific research reaches a similar conclusion. In a study of 1,551 Italian adults, variation in perceived bitterness and variants in taste-related genes were associated with liking for sweetened and unsweetened coffee. These associations help explain why removing sugar or milk can feel very different across drinkers without invoking a character judgment. Catamo et al., 2022.
Caffeine can condition flavor liking
Coffee has another unusual property: its flavor repeatedly predicts the physiological effects of caffeine. Experimental work has shown that pairing a novel flavor with caffeine can increase the flavor’s rated pleasantness over repeated exposures in habitual caffeine consumers. This is a learning mechanism, not a personality diagnosis. Yeomans, Durlach, & Tinley, 2005.
A related experiment found that caffeine reinforcement depended on habitual caffeine use and dose: in overnight-withdrawn moderate consumers, a 1 mg/kg caffeine pairing increased pleasantness for the paired flavor, whereas the same pattern was not seen in non/low consumers. Such findings show how a once-neutral or aversive flavor can acquire value because of what it predicts. Tinley, Durlach, & Yeomans, 2004.
For coffee specifically, genetic analyses have also suggested that caffeine-related biology is intertwined with whether people prefer black coffee, tea, and dark chocolate. Cornelis and van Dam found that genetically inferred caffeine sensitivity related more strongly to coffee taste preferences than their bitter-taste hypothesis predicted, which they interpreted as compatible with conditioned taste preference. Cornelis & van Dam, 2021.
Familiarity, exposure, and the whole flavor matter
Coffee is never experienced as bitterness alone. Aroma, acidity, sweetness, texture, temperature, roast character, aftertaste, and context combine into a single perceptual experience. Repeated exposure can make formerly unfamiliar features predictable, and attention can shift from an undifferentiated “bitter” impression toward more specific aroma and flavor notes.
Research on bitter/astringent foods and coffee/tea choices also shows that preference is shaped by multiple individual differences. In a large Italian study, food neophobia, sensitivity to punishment, and sensitivity to disgust were related to choosing less bitter/astringent options, while PROP taster status did not show a simple main effect on the choice index. That pattern is another reminder that bitter-food choice does not reduce to one biological or personality variable. De Toffoli et al., 2019.
For a deeper explanation of acquired liking, see Why Do People Learn to Like Bitter Coffee? Acquired Taste, Exposure, and Reward.
Identity and context can influence the choice without defining personality
Some people choose black coffee because they enjoy its flavor. Others want to taste a particular coffee without milk or sugar. Some value convenience, routine, caloric simplicity, or a familiar morning cue. Some have learned that “serious coffee” is supposed to be drunk black and may adopt that convention as part of expertise or identity. These motives can coexist in the same person and change across situations.
Contextual meaning is psychologically real, yet it is different from saying that a beverage reveals a fixed trait. A black-coffee choice can function as a habit, preference, ritual, or social signal. None of those functions licenses an inference that the drinker is callous, sadistic, independent, disciplined, minimalist, authentic, or any other stock personality type.
What Later Research Adds
A later peer-reviewed paper by Sagioglou and Greitemeyer examined broader preferences for mildly aversive or “benignly masochistic” experiences across six studies with 2,999 participants. The work reported associations between enjoyment of aversive experiences and antisocial traits such as subclinical psychopathy and everyday sadism. Bitter preference appeared as one behavioral expression within a much broader construct. Sagioglou & Greitemeyer, 2020.
That later paper strengthens the case that there may be a real, modest relationship between some aversive-stimulation preferences and some antisocial trait dimensions at the population level. It still does not turn black coffee into a psychopathy marker. The construct being studied is broader than coffee, the effects are probabilistic, and multiple mediating pathways such as sensation seeking and disgust sensitivity are relevant. Sagioglou & Greitemeyer, 2020.
A 2017 honors thesis attempted a laboratory-based partial replication of the bitter-preference finding with 40 undergraduates who actually tasted solutions. It did not support a bitter-preference/psychopathy link. Because the sample was very small and the procedure differed from the original, the thesis is best treated as limited replication evidence rather than a decisive refutation. Waymire, 2017.
The evidence base is therefore narrower than the popularity of the claim suggests. One influential peer-reviewed paper found the association with a general bitter-preference measure; the same paper showed inconsistent results for specific bitter foods; later related work found broader aversive-preference associations; and a small non-peer-reviewed replication failed to reproduce the specific psychopathy relationship. That is enough to justify continued research, not enough to justify judging a person from a mug.
Psychopathy, Psychopathic Traits, and Antisocial Personality Disorder
Popular articles often use “psychopath” as if it were a simple yes/no category. Research practice is more complicated. Psychopathy is commonly studied as a dimensional constellation of interpersonal, affective, and behavioral traits, while antisocial personality disorder is a formal diagnostic construct with its own criteria. The two overlap but are not synonyms. Anderson & Kelley, 2022.
The 2016 bitter-taste study used a brief Dark Triad questionnaire to measure psychopathy traits in community participants. That is appropriate for investigating correlations among traits, but it is not equivalent to a forensic psychopathy assessment or an individual clinical evaluation. Sagioglou & Greitemeyer, 2016.
A coffee preference therefore cannot be used to diagnose psychopathy, antisocial personality disorder, narcissism, sadism, or any other personality disorder. It cannot establish dangerousness, empathy, morality, aggression, or how someone will behave in a relationship. The appropriate inference is much smaller: in some samples, people reporting greater liking for bitterness also reported somewhat higher scores on certain trait measures.
Can Coffee Preference Reveal Personality at All?
At the individual level, coffee preference is a poor shortcut to personality. A single order has many plausible causes, and the same person may order differently across time and contexts. When researchers find a correlation between a food preference and a personality scale, that does not mean the preference is accurate enough to classify individuals.
This distinction between explanation and prediction is essential. A psychological variable can help explain a tiny portion of variance across a population while providing almost no useful information about a particular stranger. The Study 1 psychopathy model’s 2.4% explained variance is a vivid example: statistically interesting for research, practically weak as a person-reading tool. Sagioglou & Greitemeyer, 2016.
The broader literature on food behavior likewise describes a network of sensory sensitivity, familiarity, culture, reward, social learning, personality, and context rather than one-to-one mappings between foods and character. Coffee is especially complex because its taste is paired with caffeine, ritual, wakefulness, work routines, cafés, identity, and social conventions.
So the scientifically defensible answer to “What does black coffee say about your personality?” is: very little by itself. It reliably says that, in that moment, you are willing to drink that coffee without common additions. Any inference beyond that requires independent evidence about the person.
What About the “Independent, Disciplined, Minimalist” Black-Coffee Stereotype?
Current coffee-personality pages often assign black-coffee drinkers a flattering cluster of traits: independent, practical, disciplined, focused, authentic, minimalist, strong-willed, adventurous, or “no-nonsense.” These descriptions are culturally plausible stories, but they are not established psychometric profiles of people who drink black coffee.
The key problem is the same as with the psychopath headline, only the emotional direction changes. A behavioral choice can be interpreted symbolically—no additions becomes “simplicity,” a bitter flavor becomes “toughness,” and a plain order becomes “directness.” The metaphor feels coherent, but coherence is not evidence that the trait was measured, that the association is reliable, or that the drink predicts the person.
Research does show that psychological variables can relate to bitter or unsweetened food choices. For example, a large study of bitter/astringent foods and beverages found that food neophobia, sensitivity to punishment, and sensitivity to disgust were associated with choosing less bitter/astringent options. Yet this does not produce a single black-coffee personality profile, and the study did not validate common internet labels such as disciplined, independent, or minimalist. De Toffoli et al., 2019.
Sensory biology can also create behavior that looks like personality from the outside. Someone who perceives coffee bitterness less intensely may find unsweetened coffee easier to enjoy; someone with different sweet or bitter sensitivity may prefer additions. Coffee-specific genetic and phenotypic studies support individual variation in sweetened versus unsweetened coffee liking without implying a moral or character difference. Catamo et al., 2022.
Finally, black coffee can carry social meaning. A person may use it to communicate expertise, simplicity, health goals, efficiency, tradition, or membership in a coffee culture. Social signaling is real behavior, but a signal is context-dependent and partly strategic. It is not the same as a stable personality trait measured independently across situations. A person can perform a “black coffee” identity at work and still prefer sweet coffee at home.
So both negative and flattering stereotypes should be handled the same way: treat them as hypotheses about social meaning until evidence demonstrates a robust, replicated relationship with validated personality measures. The cup can participate in identity; it does not read the mind of the person holding it.
How to Read Coffee-Personality Claims Without Being Misled
First, ask what was actually measured. “Black coffee,” “coffee,” “bitterness,” “unsweetened coffee,” and “general bitter-taste preference” are different variables. A study of one cannot automatically be rewritten as a study of another.
Second, ask how personality was measured. A dimensional questionnaire score is not the same as a clinical diagnosis, a forensic classification, or an everyday label such as “psychopath.”
Third, look for the size of the relationship, not just whether it reached statistical significance. A small association can be reproducible and scientifically interesting while remaining useless for identifying individuals.
Fourth, look for converging measures. In the 2016 paper, the broad self-description “I like bitter foods and drinks” gave a different personality pattern from preferences for specific foods categorized as bitter. When methods disagree, the disagreement belongs in the conclusion. Sagioglou & Greitemeyer, 2016.
Fifth, look for replication and mechanism. Later evidence can strengthen, weaken, or refine an association. Mechanistic work on taste genetics, caffeine reinforcement, brewing chemistry, and learning shows that black-coffee preference has several credible pathways that do not require a dark-personality explanation. Cornelis & van Dam, 2021; Yeomans et al., 2005; Lang et al., 2020.
What Would Stronger Evidence Need to Show?
A convincing test of the specific “black coffee personality” claim would begin by defining the beverage precisely. Researchers would need to distinguish black coffee from unsweetened coffee, espresso from brewed coffee, roast level, brew concentration, caffeine dose, and actual perceived bitterness. A self-report checkbox labeled “coffee” cannot resolve those sensory differences.
The study would also need direct sensory measurement. Participants could taste standardized coffees with controlled brewing variables and rate bitterness, liking, aroma, and overall pleasantness. That would separate liking the concept of “bitter foods” from liking the actual sensory experience. The original 2016 study explicitly identified this distinction as a limitation of self-reported food-name preferences. Sagioglou & Greitemeyer, 2016.
Personality measurement would need equal precision: validated dimensional instruments, adequate sample sizes, preregistered hypotheses, transparent exclusions, correction for multiple testing, and replication in independent populations. Demographics, culture, habitual caffeine use, smoking, alcohol use, dietary patterns, and other variables could confound both taste preference and personality scores and should be considered explicitly.
Most importantly, a study intended to support an individual claim would have to test prediction, not merely correlation. Researchers would need to show that black-coffee preference improves out-of-sample prediction of personality beyond relevant background variables and that the effect is large enough to matter. Statistical significance alone would not meet that standard.
A causal claim would require another level of evidence. Even if black-coffee preference reliably predicted a trait, that would not show that drinking black coffee changes personality or that personality causes the preference. Plausible third pathways already exist: taste genetics, caffeine sensitivity, conditioning, familiarity, social learning, and cultural meaning. Cornelis & van Dam, 2021.
What Your Black Coffee Preference Actually Says
If you prefer black coffee, the strongest conclusion is that you prefer at least some coffee without milk, cream, sugar, or other additions. Depending on the person, that preference may reflect sensory liking, familiarity, caffeine learning, routine, convenience, dietary choices, appreciation of coffee flavor, or social and identity meanings.
It does not scientifically establish that you are a psychopath, sadist, narcissist, minimalist, purist, disciplined worker, independent thinker, health enthusiast, introvert, extrovert, or “old soul.” Those descriptions may be entertaining cultural stereotypes, but they are not validated personality assessments.
The interesting scientific story is subtler than the meme. Bitter preference may correlate modestly with some personality dimensions in some samples. Coffee preference is also shaped by taste biology, brewing chemistry, learning, caffeine reinforcement, familiarity, and context. Those influences overlap, which is exactly why one cup cannot carry the evidential weight of a personality test.
FAQ
Are black coffee drinkers more likely to be psychopaths?
Research does not justify that individual-level claim. A 2016 study found group-level associations between general bitter-taste preference and psychopathy-trait scores, but black coffee was not used as a diagnostic category. The food-specific bitter measure was also inconsistent with the general preference measure. Sagioglou & Greitemeyer, 2016.
What personality type drinks black coffee?
There is no scientifically established “black coffee personality type.” People drink black coffee for many reasons, including flavor, habit, caffeine, convenience, ritual, dietary preferences, and learned appreciation. A coffee order does not map cleanly onto a stable personality profile.
Does liking bitter food mean you are a sadist or psychopath?
No. The evidence concerns small-to-moderate statistical associations among continuous variables in groups, not deterministic classification. Many people who enjoy bitter foods will score low on antisocial traits, and many people with higher antisocial-trait scores will not prefer bitter foods.
Why did the study become a black-coffee story?
Coffee is familiar, vivid, and easy to turn into a headline. It was also one of the specific foods included among bitter items. But the study’s strongest findings concerned general liking for bitter foods and drinks, not a direct comparison of black-coffee drinkers with milk-and-sugar drinkers. Sagioglou & Greitemeyer, 2016.
Why do some people enjoy black coffee if bitterness is naturally aversive?
Adult preference can be learned. Individual taste sensitivity differs, repeated exposure changes familiarity, coffee contains rewarding caffeine, and the whole flavor includes aroma, acidity, sweetness, texture, and roast character rather than bitterness alone. Human experiments show that caffeine can condition increased pleasantness for paired flavors. Yeomans et al., 2005.
Is black coffee always more bitter than coffee with milk or sugar?
Adding milk or sweetener can reduce or mask perceived bitterness, but “black coffee” is not a standardized bitterness level. Roast, extraction, concentration, and bean chemistry strongly influence sensory bitterness before anything is added. Frost et al., 2020; Lang et al., 2020.
Can a therapist or psychologist infer personality from a coffee order?
A coffee order is not a validated personality assessment. Clinically meaningful conclusions about personality require appropriate history, context, validated measures, and professional evaluation when diagnosis is relevant. Coffee preference can be discussed as a habit, sensory preference, ritual, or social cue, but it cannot substitute for assessment.
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Coffee and Personality: What Your Coffee Preference Can and Cannot Say About You — the broader evidence owner for coffee preference and stable personality claims.
What Does Your Coffee Order Say About You? Personality Claims vs Social Signals — the social-signals owner for what coffee orders can and cannot communicate.