Nutrition and shift work

Shift working has been a long-standing feature in workplaces such as health and social care, emergency and security services as well as in many manufacturing industries. As the move towards a 24-7 economy in the UK continues, this has expanded rapidly to include areas such as retail, customer services, road transport and communications. Currently, around 18% of UK employees have some form of shift work inherent in their role and there are over 3 million UK employees who work  permanent or rotating night shifts ⁽¹⁷⁾

We know that the workplace influences diet with around 60% of food eaten during working hours ⁽⁴⁾. Shift patterns can influence eating with the potential to impact on factors such as fatigue, concentration and mood as well as on longer-term physical and mental health.

The links between diet and health in shift workers is a complex involving interactions between sleep, light exposure, circadian rhythms and even genetic predisposition. Shift workers have been found to be more likely to report at least one longstanding medical condition ⁽¹⁰⁾. There appears to be a higher prevalence of central obesity and cardiovascular disease as well as type 2 diabetes, particularly in those working rotating shifts. Some studies also suggest a great incidence of gastrointestinal disorders, some types of cancer and mental health problems ⁽¹²⁾.

Which factors might contribute to diet-related health risks in shift workers?

1. Timing of eating (chrono nutrition)

There is increasing evidence that time of eating may influence health risks in both the general population and in shift workers ⁽⁵⁾. Eating a greater proportion of one’s daily food later in the day appears to impair glucose tolerance and blood lipid levels. This is particularly true of a sub-group of people who have a particular melatonin receptor -1b gene variant (MTNR1B) ⁽⁷⁾.  The evidence is not yet strong enough to make firm recommendations as to the optimal timing of eating in shift workers but there may be some benefits in:

• Consuming the main meal earlier in the biological day e.g. before a shift starts rather than during the night.
• Taking breaks which include drinks, lighter meals and/or healthy snacks during the night (rather than avoiding food & drink at night).
•  Having a light rather than a heavy meal in 1-2 hours before bed as part of general sleep hygiene.

2. Diet quality

Focusing on the quality of the diet may be as important as timing. Food surveys have shown shift workers often report less nutritionally dense diets with lower fruit and vegetable intakes combined with higher free sugars and saturated fat consumption ^(10,11,14).

The reasons for this might include poor access to healthy food choices or vending when facilities are closed or reliance on speed convenience or sweetened caffeinated drinks to stay awake. Advice on  including foods with a lower glycaemic index (GI), reducing sugar and saturated fat, choosing healthier snacks and drinks and limiting caffeine to within recommended levels can all be useful in improving diet quality in shift workers ⁽²⁾

 3. Irregular meal patterns

Shift work, and in particular rotating shifts, can cause disruption to family life and meal patterns. Shift workers may also take fewer breaks due to lack of opportunities and facilities or as a result of fewer prompts and cues from fellow co-workers.

Irregular eating patterns have been linked to a higher risk of central obesity and impaired glucose tolerance. We also know that missing meals, eating quickly and distracted eating or grazing can lead to overeating ⁽⁶⁾.

Shift workers can be encouraged to avoid skipping meals and to spread food intake more evenly throughout the waking period with a mix of light or heavy meals, snacks and drinks.

 4. Short sleep duration

 Short sleep is a known risk factor for weight gain and shift workers may be at particular risk if sleep is disrupted by light or noise during the day. A recent study looked at overweight adults who routinely slept for less than 6.5 hours. It found that sleep hygiene interventions to increase sleep duration by 1.2 hours led to reduced appetite and a decrease in daily energy intake of 270 calories ⁽¹⁵⁾. Improving sleep quality in shift workers may therefore be a strategy to help reduce weight gain.

Workplace nutrition interventions to support shift workers

Dietary interventions may be particularly important in shift workers to mitigate some of the associated health risks ⁽¹⁵⁾. It is important to acknowledge the challenges inherent with respect to eating and shift work and to emphasise the inclusion of positive foods and patterns rather than a criticism of food choices and coping skills already in place.

Health check facilities and nutrition education tailored to shift workers, delivered at suitable times can be useful. This might include supporting dietary coping skills via group sessions or even individual 1 to 1 dietary advice for those at high risk. Practical suggestions for quick, affordable and nutrient-dense meals, snacks and drinks can be included alongside ideas for ways to transport and store food at work. Tips for planning in advance and even using communal meal leftovers are useful for promoting shared and social cooking connections.

It is also important to consider environmental factors such as access to food and drink in addition to those on personal choice. Catering and vending facilities will need to be easily accessible and provide a good variety of healthy choices at affordable prices. Shift workers may also benefit from prompts, encouragement and a workplace culture that values the importance of breaks to eat and drink. This can offer benefits not just for long-term health but shorter-term performance, safety and even mood.

How can BDA Work Ready help?

At BDA Work Ready we offer a range of evidence-based nutritional workplace interventions tailored to support the health of shift workers addressing timing, quality and regularity of eating and drinking as well as access. These might include workshops, webinars or 1 to 1 sessions. We can also provide guidance on healthy catering and vending options suitable for shift workers.

Order our 'eat well on shift' poster or fact sheets for your workers, or to enquire about any of our services please fill out the form below:

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References

1. Bonham et al CE et al. (2020) Effects of macronutrient manipulation on postprandial metabolic responses in overweight males with high fasting lipids during simulated shift work: A randomized crossover trial. Clinical Nutrition 39:369-377.

2. Bonnell et al (2017) Influences on dietary choices during day versus night shift in shift workers. Nutrients 26:193

3. Centofanti, S et al (2018) Eating on nightshift: A big vs small snack impairs glucose response to breakfast. Neurobiology of Sleep and Circadian Rhythms 4: 44–48.

4. Cowbrough K, Gardner E (2016) Nutrition at Work: Nutrition interventions in workplace health programmes: a literature review. Occup Heal Work. 13:30–6.

5. D’Annibale et al (2021) Nutri Bull.  Eating on the night shift: A need for evidence‐based dietary guidelines? - Nutrition Bulletin - Wiley Online Library (Accessed 16.3.22)

6. Garcidueñas-Fimbres ML et al (2021) Eating Speed, Eating Frequency, and Their Relationships with Diet Quality, Adiposity, and Metabolic Syndrome, or Its Components Nutrients 13:1687

7. Garaulet M et al (2022) Interplay of Dinner Timing and MTNR1B Type 2 Diabetes Risk Variant on Glucose Tolerance and Insulin Secretion: A Randomized Crossover Trial. Diabetes Care 45:512-519

8. Gibbs M et al (2014) Diurnal postprandial responses to low and high glycaemic index mixed meals. Clinical Nutrition 33:889-94.

9. Gupta CC et al (2019) Subjective hunger, gastric upset, and sleepiness in response to altered meal timing during simulated shift work. Nutrients 11(6):1352.

10. Health Survey for England - 2013 - NHS Digital ( Accessed 16.3.22)

11. Hemiö K et al. (2015) Food and nutrient intake among workers with different shift systems. Occupational and environmental medicine 72:513–20.

12. Moreno CRC et al (2019) Working Time Society consensus statements: Evidence-based effects of shift work on physical and mental health. Ind Health. 57:139-157.

13. Ogden J et al (2018) 'Snack' versus 'meal': The impact of label and place on food intake Appetite120: 666-672.

14. Peplonska B et al ( 2019). Rotating night shift work and nutrition of nurses and midwives. Chronobiol Int. 36:945-954. 

15. Tasali E et al ( 2022) Effect of Sleep Extension on Objectively Assessed Energy Intake Among Adults With Overweight in Real-life Settings: A Randomized Clinical Trial. JAMA Intern Med. Published online 7.2.22 (Accessed 16.3.22)

16. Segers, A & Depoortere I (2021) Circadian clocks in the digestive system. Nature Reviews Gastroenterology and Hepatology 18:239–251.

17. TUC (2019) Older workers powering an increase in night working ( Accessed 16.3.22)