If you prefer your coffee black, you may just be someone who likes strong flavours, takes good care of their health, or is in desperate need of a pick-me-up.
Or, you may be a psychopath.
Research from the University of Innsbruck in Austria has found that a love of black coffee is "positively associated" with traits such as psychopathy and everyday sadism.
The research examined the taste preferences of more than 1,000 adults and found that those who preferred more bitter notes in foods - like black coffee, beer, radishes, tonic water, and celery - scored higher on a series of personality questionnaires that assessed Machiavellianism.
Machiavellianism is a term used in psychology to describe personalities that are dark, psychopathic, narcissistic, and sadistic.
Um ... yikes.
And this is not the first time research has found a link between taste and personality.
Previous studies have shown sweet taste experiences increase "agreeableness" and eagerness to help, while bitter taste experiences increase hostility and elicit harsher moral judgments.
So the next time you're standing in line at your local café and the person in front of you orders a strong, black coffee - you have been warned!