A hormone called FGF21 that is secreted by the liver after eating sweets may determine who has a sweet tooth and who doesn’t, according to a study in Cell Metabolism published May 2. Researchers at the Novo Nordisk Foundation Center for Basic Metabolic Research at the University of Copenhagen found that people with particular variants of the FGF21 gene were about 20% more likely to be top-ranking consumers of sweets and candy, such as ice cream, chocolate, and gumdrops than their counterparts in the study.