Night‑Shift Work, Short Sleep, and Obesity
Summary
This cross-sectional study compared 200 healthcare workers in Brazil to see how night shifts affected sleep and obesity. Night-shift workers were older, slept fewer hours, and had significantly higher body weight, BMI, and abdominal circumference than day-shift workers. They also experienced more social jetlag (a mismatch between work schedules and natural sleep patterns). Night workers had nearly three times greater odds of abdominal obesity, even after adjusting for age and gender. Quality of life scores did not differ between groups.
Why It Matters For Night Shift Workers and Night Owls
This study shows that working nights can raise the risk of abdominal obesity, likely because shorter and more irregular sleep disrupts recovery. The findings highlight that it’s not just what you eat or how much you exercise — your work schedule itself can influence weight gain. For night-shift workers, protecting sleep time on both workdays and days off, and reducing social jetlag where possible, may help lower the risk of obesity over time.
Notes
Open access review.