The present article analyses the influence of positive and negative affect on health. The sample consists of 113 first-year undergraduates (76.1% female, 21.2% male and 2.7% unknown), with an age range of 18 to 27 years (M = 19.12, SD = 1.77). Participants were asked to fill out the Positive and Negative Affect Scale (PANAS), physical health was measure with one scale of the General Health Survey (SF-20), one month and one year later of filling out the PANAS. We used a structural equation modelling to test longitudinal relationships between positive and negative affect and health. As we expected, PA and NA predicted health measured one month later and one year later, respectively. Longitudinal analyses over successive 1-month and 1-year intervals revealed reciprocal effects between health and negative and positive affect. The implications for research on health and emotions are discussed.