What This Means
This study looked at 52 men working at a defense factory in Türkiye, some on fixed daytime schedules and some on rotating shifts. The researchers compared what they ate (using three 24-hour food recalls), how inflammatory their diets were (using the Dietary Inflammatory Index, or DII), and how well they slept (using the Pittsburgh Sleep Quality Index). They also took body measurements and blood tests.
Rotating shift workers ate more overall, including more fat, saturated fat, cholesterol, and fructose, and also more of certain vitamins and minerals such as vitamin A, folate, iron, calcium, and phosphorus. However, the inflammatory potential of the diet, as measured by DII, was not meaningfully different between the two groups. Across all participants, a more inflammatory diet was linked with worse sleep, including shorter sleep duration and more daytime dysfunction. But once factors such as age, BMI, smoking, physical activity, and work schedule were taken into account, the link between DII and overall sleep quality was no longer statistically significant.
This research suggests that diet and sleep problems may occur together in shift workers, but it cannot show that one causes the other. The study was small, included only men from one workplace, and measured everything at a single point in time, so the findings should be treated cautiously.