A recent review, pooling results from 28 studies, has looked at the associations between shift work patterns and the risks of specific types of obesity. It found that shift workers had a higher frequency of developing abdominal obesity than other obesity types.
Abdominal obesity is characterised by a change in body shape and fat accumulation in the abdomen which surrounds the internal organs. It is commonly associated with altered metabolic profiles such as insulin resistance and abnormal lipids.
In particular, permanent night workers (covering the period between 24.00 and 05.00) demonstrated a 29% higher risk than rotating shift workers. Reasons suggested for this is that permanent night shift workers are more frequently exposed to light at night which disrupts circadian rhythms. They may also have more disrupted daytime sleep patterns leading to an accumulation of chronic sleep debt. Sleep deprivation is a mechanism that can lead to increased body weight.
Employees in the manufacturing industry were found in the review to have a relatively higher risk of obesity/overweight. Long working hours (commonly 10 hour shifts) and the need to maintain a relatively high calorie intake overnight to accommodate their heavy workload were proposed as potential reasons that require further investigation. A study by Seychell & Reeves (2017) on nurses in Malta found that those working night-shift consumed more energy compared to day nurses (night-shift nurses 1,963 ± 506 kcal; rotating-shift nurses 2,065 ± 655 kcal; day nurses 1,722 ± 486 kcal; p = 0.04).
The authors call for modifications in working schedules to avoid prolonged exposure to long-term night shifts. Additionally, all shift workers need to be aware of the potential for developing abdominal obesity and supported in developing healthy eating patterns to combat its progression. For more information on how BDA WorkReady can help contact us on 0121 2008080 or email email@example.com
Sun M, Feng W, Wang F et al (2017) Meta-analysis on shift work and risks of specific obesity types. Obesity Reviews . http://onlinelibrary.wiley.com/doi/10.1111/obr.12621/abstract?campaign=wolearlyview
Seychell J & Reeves S (2017) The effect of shift work on the diet of accident and emergency nurses at a general hospital in Malta, Nutrition & Food Science, Vol. 47 Issue: 2, pp.165-174.