The aim of this doctoral dissertation was to investigate the relationship between interoception, alexithymia, emotion regulation, and their role in the prevention of obesity. Interoception is the ability to perceive the internal bodily states, such as cardiac, respiratory, and gastrointestinal signals. Alexithymia is the difficulty in recognizing and labeling emotions. A set of six studies using correlational and experimental approaches, quantitative and qualitative methods, explored five research questions. First, the association between interoception and alexithymia was examined. Second, the protective role of interoception in emotion regulation was tested. Third, the role of alexithymia in emotion regulation was studied. Fourth, a methodological question was addressed trying to understand if the measurement of interoception is valid. Fifth, the role of individual differences and levels of interoception and alexithymia in attention bias toward food was examined.