Shift Work and Health Impacts

Shift work is a significant occupational and public health challenge in the UK, with approximately 14% of the workforce engaged in night work or irregular shift patterns — representing more than four million individuals. Extensive research demonstrates that working outside normal daytime hours is linked to a range of adverse long‑term health outcomes.

Employees undertaking night shifts or rotating work patterns are at increased risk of cardiovascular disease, obesity, type 2 diabetes, gastrointestinal disorders, sleep disturbance, and poor mental health. There is also evidence linking long‑term shift work to certain cancers. The World Health Organization has classified shift work that disrupts circadian rhythms as a probable carcinogen, reflecting the biological impact of sustained disruption to the normal sleep–wake cycle.

Large population studies support these findings. A major meta-analysis published in 2018 found that shift workers were significantly more likely to experience cardiovascular events than day workers, with risk increasing progressively with longer duration of exposure. Evidence suggests that cardiovascular risk continues to rise after approximately five years of ongoing shift work.

The consequences of shift work are not limited to physical health. Disruption to family routines, social relationships, and recovery time often leads to increased stress, fatigue, and reduced overall wellbeing. From a public health perspective, shift work influences both chronic disease prevention and mental wellbeing, as well as wider determinants of health such as working conditions. These impacts also carry economic costs for organisations through sickness absence, presenteeism, and reduced productivity.

Dietary and Nutritional Impacts of Shift Work

Dietary behaviour is a key mechanism through which shift work affects health. Research involving UK healthcare shift workers with type 2 diabetes has demonstrated that eating habits during night work are heavily shaped by environmental and organisational factors, rather than knowledge or motivation alone. Limited access to healthy food overnight, poor facilities for food storage or preparation, time pressures, and fatigue all influence food choices.

As a result, workplace interventions focused solely on education are unlikely to be effective. Employers should prioritise practical and environmental support, ensuring that healthier food and drink options are available, affordable and accessible at all working hours, particularly overnight.

Observational research consistently shows lower diet quality in shift workers, including higher consumption of sugar‑sweetened drinks, alcohol, and foods high in saturated fat, alongside lower intakes of vegetables and other nutrient‑dense foods.

In emergency and frontline healthcare roles, further challenges have been identified. Studies indicate that night‑shift workers often consume fewer calories, macronutrients, and fluids than during day shifts. Prolonged fasting periods and reduced meal frequency suggest that altered eating patterns, rather than total calorie intake alone, contribute to adverse metabolic outcomes.

Similar challenges are seen in other safety-critical occupations. Research involving UK police officers found that diet quality was poorest during night shifts, with a high prevalence of overweight and obesity. Participants described disrupted meal timing, greater reliance on convenience foods, and barriers such as limited time, reduced motivation, and cost.

Night‑shift work is also associated with circadian misalignment, characterised by more frequent eating episodes, shorter fasting periods, increased fat intake, and reduced exposure to daylight. Together, these factors are thought to increase the risk of obesity, cardiometabolic disease, and poorer long‑term health.

What Can Employers Do to Support Shift Workers?

Employers play a critical role in reducing health risks associated with shift work. Effective support requires a combination of legal compliance, fatigue management, workplace design, and access to occupational health support.

Legal Compliance

Employers should ensure full compliance with the Working Time Regulations, including:

• A minimum of 11 hours’ rest in each 24‑hour period
• An average 48‑hour maximum working week (unless workers opt out)
• A limit of 8 hours’ work in any 24‑hour period for night workers in safety‑sensitive roles
• Paid annual leave of at least 5.6 weeks
• A 20‑minute rest break for shifts longer than six hours

Workers should also be offered appropriate health assessments before being assigned to night work, with follow‑up reviews where required.

Shift Scheduling and Fatigue Management

Good shift design can significantly reduce fatigue‑related risk. Employers should:

• Use forward‑rotating shift patterns (day → evening → night) where possible
• Limit the number of consecutive night shifts
• Ensure protected breaks, sufficient recovery time, and predictable schedules
• Train supervisors to recognise signs of fatigue and identify safety‑critical periods

Workplace Environment and Nutrition

The working environment should support recovery and safe performance, including:

• Safe travel arrangements, appropriate lighting, ventilation, and temperature control
• Suitable rest facilities for breaks and, where appropriate, short restorative naps
• Access to healthy food and drinks 24/7, with facilities for storage, reheating, and preparation
• Support for meal planning, hydration, and appropriate meal timing to reduce metabolic risk

Health, Wellbeing and Training

A comprehensive approach should also include:

• Access to occupational health services, mental health support, and fatigue or sleep education
• Reasonable adjustments for vulnerable workers, including those who are pregnant or managing long‑term health conditions
• Promotion of physical activity and wellbeing initiatives that are accessible across all shift patterns, not only standard daytime hours

Let’s protect your team from the hidden risks of shift work. Contact us at [email protected] or visit kaysmedical.com to explore our health and wellbeing support for shift workers.