Since the 1970s, consumers in the US and the EU have been influenced by the publication of occasional studies purporting to link foods, food ingredients, and food additives with a variety of health concerns. We have seen food trends emerge from weak or poorly designed studies, leading to objectification of fats, salt, animal proteins, preservatives, and even methods of cooking (think: microwaves).
Two famous examples include the Feingold Diet, which arose from studies going back to 1968 that purported to link hyperactivity in children to food additives such as preservatives and synthetic colorants. In 2004, the Southampton Study purported to show the same linkages.