Approximately 17% of the workforce of the European Union is now engaged in shift work(1), moving away from the typical working week. Shift work has been reported to adversely affect the health of workers, leading to a higher risk of overweight/obesity and other chronic diseases(2). The increased health risk may be linked to some of the observed lifestyle changes associated with shift work(3). This study aimed to compare the lifestyle and dietary characteristics of normal weight and overweight/obese shift workers. 
A cross-sectional study was conducted on 1,072 consenting shift workers using a 15-minute telephone questionnaire developed from qualitative research with shift workers(4,5). Body Mass Index (BMI, kg/m2) was calculated using self-reported height (m) and weight (kg) measurements, and data were analysed according to WHO BMI categories: Normal weight, BMI 18.5-24.9 kg/m2 vs. overweight/obese BMI >25 kg/m2.
Within the group of shift workers 43.7% were classed as overweight or obese. Univariate analysis indicated that being male, being in the middle or older age group, consuming <5 portions of fruit and vegetables per day and having a medium-high fried food consumption was associated with being Ow/Ob. Smoking and exceeding units of alcohol per week were associated with having a normal BMI. Following multivariate analysis being male [p<0.001, OR=2.31, 95% CI (1.73-3.09)] and being in the middle or older age groups were independently associated with overweight or obese BMI [p<0.001, OR=2.54 95% CI (1.85-3.49) and p<0.001, OR=2.89 95% CI (1.87-4.48) respectively]. Unhealthy dietary behaviours associated with BMI >25 kg/m2 included medium-high consumption of fried food [OR=1.97, 95% CI (1.48-2.63)] and eating less than the recommended number of portions of fruit and vegetables per day [OR=1.38, 95% CI (1.07-1.79)]. Exceeding recommended units of alcohol per week remained associated with a normal BMI [OR=0.62, 95% CI (0.38-0.99)]. Smoking was not associated with a normal BMI following multivariate analysis.
In conclusion, this study indicates that shift work affects both the lifestyle and dietary characteristics of shift workers regardless of BMI. Some dietary choices play a role in overweight/obesity. Male and middle/older age shift workers may benefit from targeted dietary and lifestyle advice to protect against overweight and obesity. The effect of alcohol consumption on the BMI of shift workers warrants further research.

07. An investigation into the lifestyle and dietary characteristics of normal weight versus overweight and obese shift workers on the island of Ireland