Seasonality of food groups and total energy intake: a systematic review and meta-analysis

BACKGROUND/OBJECTIVES: The aim of this systematic review and meta-analysis was to assess the effect of season on food intake from selected food groups and on energy intake in adults. SUBJECTS/METHODS: The search process was based on selecting publications listed in the following: Medline, Scopus, Web of Science, Embase and Agris. Food frequency questionnaires, 24-h dietary recalls and food records as methods for assessment of dietary intake were used to assess changes in the consumption of 11 food groups and of energy intake across seasons. A meta-analysis was performed. RESULTS: Twenty-six studies were included. Articles were divided into those reporting data on four seasons (winter, spring, summer and autumn) or on two seasons (pre- and post-harvest). Four of the studies could be utilized for meta-analysis describing changes in food consumption across four season scheme: from winter to spring fruits decreased, whereas vegetables, eggs and alcoholic beverages increased; from spring to summer vegetable consumption further increased and cereals decreased; from summer to autumn fruits and cereals increased and vegetables, meat, eggs and alcoholic beverages decreased; from autumn to winter cereals decreased. A significant association was also found between energy intake and season, for 13 studies reporting energy intake across four seasons (favors winter) and for eight studies across pre-and post-harvest seasons (favors post-harvest). CONCLUSIONS: The winter or the post-harvest season is associated with increased energy intake. The intake of fruits, vegetables, eggs, meat, cereals and alcoholic beverages is following a seasonal consumption pattern and at least for these foods season is determinant of intake.