Seasonal eating patterns in Norway: a non-clinical population study.

Seasonal deviations in normal eating habits have been associated with seasonal affective disorder (SAD) and bulimia nervosa (BN). Two studies on seasonal variation in eating habits are reported in this paper. In Study 1, seasonal patterns of eating disturbances were measured cross-sectionally in 6313 participants using an eating disturbance scale (EDS-5) and a modified version of the Seasonal Pattern Assessment Questionnaire (SPAQ). Eating disturbance scores were predicted by seasonal sensitivity scores from the SPAQ, gender, age, and light. Study 2 used a longitudinal design in which 908 participants were given the EDS-5 every month from November 1993 to January 1995. Scores on the EDS-5 fluctuated with the season of the year, with higher EDS-5 scores in winter and lower in summer. The results suggest that seasonal fluctuations affect only a subset of the total population.