Characterising the impact of shift work on diet and glucose variability in healthcare employees living with type 2 diabetes. The shift‐diabetes study

Aims: To characterise differences in dietary intake, glucose variability, and activity in free-living healthcare shift workers with type 2 diabetes (T2D) across varying work conditions. Methods: Healthcare shift workers with T2D were monitored over 10 days, covering night shifts, day shifts, and rest days. Data were collected using blinded continuous glucose monitoring, activity trackers, and diet/sleep diaries. Within-person comparisons were made for mean glucose (MG), coefficient of variation (CV), mean absolute glucose change (MAG), mean amplitude of glycaemic excursion (MAGE), continuous overlapping net glycaemic action (CONGA), dietary intake (food choices, nutrient intake), and activity/rest periods. Results: The study sample (n = 37; 89.2% women) were mainly employed as nurses or midwives (62.2%). Energy intake was highest (2199 kcal SD 648) on a day when a night shift was worked. Percentage of energy intake from sweet snacks was higher on a night shift compared with a rest day after a night shift (13.4 SD 12.0% vs. 7.8 SD 11.8%, p = 0.013). Night shifts had the highest eating occasions (7.0 SD 2.2) and rest after night (RAN) the lowest (3.4 SD 1.6), p < 0.001. No differences were reported for MG, MAGE, or CV. MAG and CONGA were higher for night shift compared with RAN shift (p = 0.029). Step counts were higher on night shift days (13,775, SD 4270 p = 0.016), and participants were awake longer (22.2 h SD 2.4 h, p < 0.001) compared with other day types. Conclusions: Night shifts are associated with prolonged wakefulness, increased activity, and distinct dietary behaviours. Tailored interventions are needed to support night shift workers with T2D in managing their condition effectively.