But new theories about what causes migraines could do something to relieve the notoriety chocolate has gained in the field.
"If we go back and look at what we assume would trigger a migraine, a lot of those things were not triggers at all but were, in the case of food, cravings that occurred as part of the migraine but were misinterpreted as the cause," said Dr. Joel Saper, director of the Michigan Headache and Neurological Institute..
In other words, eating chocolate an hour before an imminent migraine might lead a person to believe that the chocolate caused the migraine.
"The human body might crave things because we know it will alleviate [pain]," said Paul Durham, director of the Center for Biomedical and Life Sciences at Missouri State University and author of the study on cocoa powder preventing cellular inflammation in rats. "When we tried to stimulate the [pain] nerves, compounds or chemicals in cocoa might block that pain."
Doctors aren't prescribing chocolate bars to heart patients or migraine sufferers yet, but Katz said he can envision a recommendation to habitually eat dark chocolate.
"It's not just giving people a license to do what they're already doing," Katz said. Americans already eat about 12 pounds of chocolate per year, most of which is the less beneficial milk chocolate. "But if they need a nudge to switch over to the dark side, this is a place science provides us to go."
No guidelines have yet been determined about how to consume dark chocolate to maximize the health benefits. It is not clear how often and how much chocolate people should eat before the excess calories, sugar and subsequent weight gain becomes a problem, and this is one area where research could move forward.
Other areas for further research include expanding on some preliminary studies on how the antioxidants in chocolate could be harnessed to fight chronic diseases and cancer, as well as how food combinations -- like chocolate eaten with fruits and nuts -- might affect health.
"This is tougher because there are no surrogate markers [of improvement] like there are with heart studies," Katz said. "In general, foods that are good for us are really just foods that are good for us and you can't take care of just one organ at a time. If you're cultivating health, you are reducing the risk of all the bad stuff."