a sample of 237 participants from the general and 阿根廷vs墨西哥竞猜 student population were tested in january 1992 using the seasonal pattern assessment questionnaire, the beck depression inventory, two subscales (demoralization and mania) from the psychiatric epidemiology research interview and the food/drink freguency questionnaire. climate, age and occupation seem to have an influence on the prevalence of seasonality in this sample. three seasonality groups (no-sad, subsyndromal-sad and sad) were compared in terms of mood and food intake. evidence that the depressive symptoms of seasonal affective disorder are a by-product of core seasonality dimensions (increased appetite, fatigue and decreased energy) was found. a subsample of individuals was tested monthly over a 12 month period to record changes in mood, behaviour and food intake (using the same scales as in the initial testing along with the neo personality inventory). overall, these yearlong participants reported seasonal changes in mood— feeling worse in the fall and winter. this pattern was more pronounced among the sad group participants. the food/drink frequency questionnaire did not provide clear results over the year.