Shift Work & Diet
Compared to day workers, shift workers are at a higher risk of many diet-related chronic conditions, including obesity, cardiovascular disease (CVD), and type 2 diabetes. Shift work that includes overnight shifts disrupts the circadian biological clock governing the body’s internal regulation of sleep and wake times, which in turn affects energy metabolism and may promote weight gain. Eating during nighttime hours, when the body should be asleep, generates an exaggerated glucose and lipid response compared with the same meal eaten during the day. When this occurs long-term, changes in glucose and lipids are risk factors for cardiovascular disease. For the most part this is not due to a change in calorie intake, but rather when those calories are consumed, and the type of calories. It is all but impossible to advise complete avoidance of food at night for many shift workers. But we must encourage and give access to foods that are less detrimental to the cardiovascular system.
So what should we be recommending shift workers who are working nocturnal hours eat? Moderate amounts of protein, and low glycemic foods such as vegetables, nuts, seeds & some fruits. This could look like meat and salad, hard boiled eggs, a small tin of tuna, chicken soup, hummus etc... As you can see this is not what is often available, especially for those living away from home in camps for their work. Often there are lots of inexpensive, high glycemic foods available, such as cereals, sandwiches, cakes, biscuits etc.
It is not only physical health that is impacted by shift work. Among male workers, evening and night shift workers had a significantly increased risk of suicidal ideation compared to day workers after adjusting for demographics, lifestyle factors, comorbidities, number of work hours, and occupational. Mental health suffers. That may sound like it is inevitable but in reality there is much we can do to support mental health of shift workers.
Diet is considered one of the most important factors impacting on the human gut microbiome.
Recent research efforts have highlighted how the rotation between day and night leads to a higher calorie or glycaemic load diet. Shift workers tend to eat foods with a high energy intake to stay awake during the shifts, e.g. caffeine and high sugar foods; these become part of their diets as they provide quick boosts of energy in order to improve alertness during their shifts. These shifts in foods at night affect our gut microbiome. Mounting evidence suggests a role for the gut microbiota in modulating brain physiology and behaviour, through bi-directional communication, along the gut-brain axis. As such, the gut microbiota represents a potential therapeutic target .The gut microbiome is integral to neurotransmitter production. In particular serotonin and GABA. Therefor the diet has a direct role on mental health. Making sure there are plant based fibres included in the diet as well as fermented foods can help to maintain gut bacteria levels.
In clinic I see a lot of shift workers. Some are aware of the links between diet, cardiovascular disease & poor mental health, but unfortunately many are not. In our mining regions, many people are suffering poor health, simply due to camp food not being seen as a priority for the health of the workers. I am sure this is not a deliberate failing, simply a cost cutting exercise that is not fully considered. Imagine the savings to business with fewer employee sick days, better physical & mental health, and the ability of the work force to work in their positions for longer...
The long term savings would be immense. I am sure the cost of better food would soon be covered. But like many institutions, think aged care, school lunches, hospital foods - the long term advantage is not the main consideration. Short term costs decide. Changing this is something I think really needs to be addressed with a longer term vision, as healthy happy employees are far less costly than sick ones..... Lesley x
Bonnell, E., Huggins, C., Huggins, C., McCaffrey, T., Palermo, C., & Bonham, M. (2017). Influences on Dietary Choices during Day versus Night Shift in Shift Workers: A Mixed Methods Study. Nutrients, 9(3), 193. https://doi:10.3390/nu9030193
Di Stefano, A., Scatà, M., Vijayakumar, S., Angione, C., La Corte, A., & Liò, P. (2019). Social dynamics modeling of chrono-nutrition. PLoS computational biology, 15(1), e1006714. https://doi.org/10.1371/journal.pcbi.1006714
Kim, K. K., Lee, K. R., Suh, H. S., Ko, K. D., & Hwang, I. C. (2019). Association between shift work and suicidal ideation: data from the Korea National Health and Nutrition Examination Survey (2008-2016). Scandinavian journal of work, environment & health, 45(5), 458–464. https://doi.org/10.5271/sjweh.3812
Navas-Carretero, S., Abete, I., Zulet, M. A., & Martínez, J. A. (2011). Chronologically scheduled snacking with high-protein products within the habitual diet in type-2 diabetes patients leads to a fat mass loss: a longitudinal study. Nutrition journal, 10, 74. https://doi.org/10.1186/1475-2891-10-74
Van de Wouw, M., Walsh, A. M., Crispie, F., van Leuven, L., Lyte, J. M., Boehme, M., Clarke, G., Dinan, T. G., Cotter, P. D., & Cryan, J. F. (2020). Distinct actions of the fermented beverage kefir on host behaviour, immunity and microbiome gut-brain modules in the mouse. Microbiome, 8(1), 67. https://doi.org/10.1186/s40168-020-00846-5