A recently published study suggested black coffee may be the preferred pick-me-up for psychopaths everywhere, but the beverage may be getting a bad rap. Researchers who conducted the study didn't offer actual foods and beverages to their subjects to test their reactions, but instead asked about taste preferences. As Gizmodo points out, people are liars, and "the things we say about our food preferences are not only very changeable, they also bear very little on how we actually behave."
The researchers surveyed nearly 1,000 people for the study, split into two groups: students and prison inmates. The groups self-reported on their taste preferences and also completed personality questionnaires. The researchers claim that the study "provide[s] the first empirical evidence for the hypothesis that bitter taste preferences are linked to malevolent personality traits," particularly "everyday sadism and psychopathy."
But because the subjects could be making up their taste preferences to shape their self perception, there really isn't a way to link coffee and other bitter comestibles with psychopathy. So go ahead and enjoy that dark cup of joe. It doesn't really mean you're dark and disturbed, but if that's what you want people to think, there's a study to back you up.