Eating on the night shift: A need for evidence-based dietary guidelines?

Increasing 24-h demand for products, services and health care is resulting in a substantial portion of the workforce engaging in shift work. Observational studies suggest an association between shift work exposure and increased incidence of cardiometabolic disease. Shift workers report less healthy diets compared to day workers. As diet is a modifiable behaviour, it is important to understand how it might mediate the relationship between shift work and health. We reviewed online dietary advice for shift workers by searching for existing guidelines for shift workers published by websites of credible sources, for example institutions or government agencies. Based on the 26 guidelines retrieved, the most common categories of advice were eating patterns (n = 25), general healthy eating and/or specific food groups (n = 22), control of caffeine intake (n = 23) and maintaining hydration/fluid intake (n = 17). Although the majority of publicly available advice for shift workers follows general healthy eating guidelines, there are inconsistencies in the recommendations around the frequency of eating and snacking. Few studies have investigated modification of diet quality in shift workers. With the goal of adding to the evidence base, the Shift-eat study is a feasibility trial designed to test whether dietary intakes in line with UK healthy eating recommendations during night work improve markers of health (interstitial glucose and heart rate variability) in free-living shift-working employees. Shift work is unavoidable and necessary for many industries. With an increasing section of the population employed in jobs requiring shift work, consistent dietary guidance based on evidence from shift-working populations is urgently needed to support maintenance of health and wellbeing in employees working outside standard daytime hours.