It may be concluded that 12/24 shift system might give rise to insulin resistance and oxidative stress. Additionally, workers in this system may under risk of systemic inflammatory response. Working hours must be arranged in accordance with the physiological rhythm.

Objective: Rotating shift is known to disrupt circadian rhythms. The 12/24 shift system, with frequent day–night rotations and the ergonomic shift system (ESS), with 90% less rotations were compared for their impacts on oxidative stress, inflammation, and platelet activation by using pentraxin 3 (PTX3), urinary 15-isoprostane F2t, and 11-dehydrotromboxane B2 (11-DTB2). Methods: All tests were performed by enzyme linked immunosorbent assay (ELISA). Unpaired t test and Pearson correlation analysis were employed. Results: Two hundred twenty 12/24 and 198 ESS workers were included. Plasma PTX3 and urinary 15-isoprostane F2t levels were not different between groups. Urinary 11-DTB2 in 12/24 workers were found significantly higher compared with ESS workers (P < 0.0001). A weak but significant correlation was found between urinary 15-isoprostane F2t and urinary 11-DTB2 levels (r = 0.17, P = 0.001). Conclusions: 12/24 rotating shift was found to cause platelet activation disturbances.