The positive effects of the Mediterranean diet on healthy living are widely known, while the health effects of religious fasting have received increased attention during the last decade. However, no study has focused on the consumption of ultra-processed foods (UPFs) in such populations. Therefore, our aim was to investigate UPF intake and its association with metabolic syndrome (MetS) in a Christian Orthodox church (COC) religious fasting population in Greece. In this cross-sectional study, 400 individuals who follow the Mediterranean diet were included, stratified as COC fasters and non-fasters. Dietary intake data were collected via three 24 h diet recalls and a monthly food frequency questionnaire (FFQ). The NOVA food classification system was used to identify the level of processing and categorize all food items. Fasters consumed significantly less chicken, turkey, and beef and significantly more seafood, fish, snails, soy products, and fresh fruits, in terms of unprocessed or minimally processed foods, as well as significantly more fried potatoes and olives in terms of processed foods when compared with non-fasters. Regarding UPFs, a significantly lower intake of pork sausages, ketchup, and mustard as well as a significantly higher consumption of margarine and tarama dip were recorded in fasters compared with non-fasters. Fasters with MetS more frequently consumed UPFs (such as cheese pastries, biscuits, and cakes) than fasters without MetS (p < 0.05 for all comparisons). Similarly, non-fasters with MetS had an increased intake of UPFs (such as Cypriot bread and Coco Pops breakfast cereals) than non-fasters without MetS. Future research should focus on UPF consumption and its associations with clinical outcomes in such populations, thus providing further data for the potential health effects of COC fasting.
Keywords: Christian Orthodox church fasting; NOVA; metabolic syndrome; processed foods; ultra-processed foods; unprocessed or minimally processed foods.