Objectives Shift work may contribute to unhealthy eating behaviors. However, the evidence is built mainly on comparisons of eating behaviors between shift and non-shift workers. Growing research has suggested daily experiences and exposures may contribute to daily fluctuations in people’s food consumption. The purpose of this study was to examine within-person associations between shift work and same- and subsequent-day empty calorie food/beverage consumption.

Methods This was a 14-day intensive longitudinal study using ecological momentary assessment. A convenience sample of 80 hospital registered nurses working a rotating shift in Taiwan completed a 21-item food checklist assessing their empty food/beverage consumption (ie, fast/fried food, sweet and salty snacks, sugar-sweetened beverages) four times at random daily. Daily shift work (ie, day, evening, or night shift) was derived from the registry-based work schedule. Three-level mixed-effects regression models were employed for hypothesis testing.

Results A total of 77 participants with 2444 momentary assessments were included in the final analysis. The results suggested that participants on night compared to day shifts had higher likelihoods of fast/fried food intake [adjusted odds ratio (OR_adj) 1.7, 95% CI 1.2–2.6] and sugar-sweetened beverage consumption (OR_adj 1.5, 95% CI 1.0–2.1). However, there were no significant associations between shift work and subsequent-day empty calorie food/beverage consumption.

Conclusions Night shift work is associated with same-day increased empty calorie food/beverage consumption among workers. Strategies that help to prevent unhealthy eating behaviors on night shifts may help to reduce rotating shift workers’ empty calorie food/beverage consumption and ultimately improve their health.

Key terms beverage consumption; calorie; circadian rhythm; eating behavior; ecological momentary assessment; empty calorie; empty calorie food; food consumption; shift work; shift work relationship; shift worker

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