The Future of Shift Work: Circadian Biology Meets Personalised Medicine and Behavioural Science

Abstract

Shift work is commonplace in modern societies, and shift workers are predisposed to the development of numerous chronic diseases. Disruptions to the circadian systems of shift workers are considered important contributors to the biological dysfunction these people frequently experience. Because of this, understanding how to alter shift work and zeitgeber (time cue) schedules to enhance circadian system function is likely to be key to improving the health of shift workers. While light exposure is the most important zeitgeber for the central clock in the circadian system, diet and exercise are plausible zeitgebers for circadian clocks in many tissues. We know little about how different zeitgebers interact and how to tailor zeitgeber schedules to the needs of individuals; however, in this review we share some guidelines to help shift workers adapt to their work schedules based on our current understanding of circadian biology. We focus in particular on the importance of diet timing and composition. Going forward, developments in phenotyping and "envirotyping" methods may be important to understanding how to optimise shift work. Non-invasive, multimodal, comprehensive phenotyping using multiple sources of time-stamped data may yield insights that are critical to the care of shift workers. Finally, the impact of these advances will be reduced without modifications to work environments to make it easier for shift workers to engage in behaviours conducive to their health. Integrating findings from behavioural science and ergonomics may help shift workers make healthier choices, thereby amplifying the beneficial effects of improved lifestyle prescriptions for these people.

Nutritional and Behavioral Approaches to Body Composition and Low-Grade Chronic Inflammation Management for Older Adults in the Ordinary and COVID-19 Times

“…Such behaviors are often not possible for shift, essential and front-line workers whose numbers, as well as the need for them, are at the steep upsurge in the COVID-19 pandemic. Other than trying to establish regularity in everyday activities when possible or optimize the work schedules of shift workers depending on their chronotypes (morning/evening), there are some general nutritional and behavioral practices that might attenuate adverse consequences of circadian misalignment, as recently reviewed in [ 101 , 102 ]. In this context, intermittent fasting (IF) and time-restricted eating (TRE) are receiving more attention, not just from the perspective of weight loss, but also as ways to achieve some other metabolic benefits, especially important in shift and front-line workers in whom adjusting the timing, frequency, and kind of food consumption is critical.…”

“…Ketogenic diets were also investigated and showed some benefits for metabolic health, namely, glucose tolerance [ 102 ]. Additionally, some amino acids were investigated as supplements, including tryptophan (precursor for melatonin), serine, ornithine, and glycine, showing improvement in sleep quality and efficiency, shortened sleep latency and reduced wake-time fatigue [ 101 ].…”

“…Creatine was found to increase alertness and help during lack of sleep episodes when taken earlier during the active phase and with the first meal consumed. Caffeine, critical for alertness and cognitive functions (especially in shift workers), is not discouraged, but is recommended in smaller doses; every 2 h with the last consumption at least seven hours before the sleep time [ 101 ]. The adherence to these recommendations obviously depends on each individual’s preferences and work/family structure, as well as social, economic and other lifestyle circumstances.…”

Current and Future Perspectives on Light Therapy Using Wearable Devices

“…Although such changes have made life more comfortable, they have harmful effects on the sleep pattern, duration, and quality [11]. Approximately 20% of the population work outside of traditional working hours [12] and have various schedules, such as early working hours, 12-hour work shifts, and night work. Such schedules lead to excessive sleepiness and sleep disruption [13].…”

DAILY—A Personalized Circadian Zeitgeber Therapy as an Adjunctive Treatment for Alcohol Use Disorder Patients: Study Protocol for a Randomized Controlled Trial

“…Among those are brain areas that are involved in motivational responses to food and the SCN ( 51 , 52 ). Consequently, strictly timed food has already been suggested as chronotherapeutic approach to improve circadian disruptions in populations such as shift workers ( 53 , 54 ).…”