In the second part with Prof. Frank Scheer (Division of Sleep and Circadian Disorders, Brigham and Women's Hospital at Harvard Medical School, USA), we discuss what a night-shift worker could consider doing acutely (preceding, during, and following a shift) and chronically (when working years of shift schedules) to minimize health risks. In this context, we consider concepts like "sleep banking", when to exercise, caffeine ingestion, what to eat, light exposure strategies & more. We highlight which practical tools are supported by scientific evidence, whereas others seem promising but require further investigation. Lastly, Frank shares his view on how this research field around the health risks of shift work could in the long run achieve guideline changes for shift workers and how labor sectors that are dependent on shift work could be stimulated to improve working conditions.

Literature underlying practical recommendations:

Banking Sleep: Realization of Benefits During Subsequent Sleep Restriction and Recovery (Rupp et al. 2020)

https://academic.oup.com/sleep/article/32/3/311/3741695

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

https://doi.org/10.2337/dc21-1314

Effects of caffeine on human behavior (Smith 2022)

https://doi.org/10.1016/S0278-6915(02)00096-0

Blue-blockers reduce melatonin suppression:

Blue Blocker Glasses as a Countermeasure for Alerting Effects of Evening Light-Emitting Diode Screen Exposure in Male Teenagers (van der Lely et al. 2014)

https://www.jahonline.org/article/S1054-139X(14)00324-3/fulltext

Rods and cones also play a role for light suppression on melatonin etc.

S-cone contribution to the acute melatonin suppression response in humans (Brown et al. 2021)

https://onlinelibrary.wiley.com/doi/full/10.1111/jpi.12719

Circadian Photoentrainment in Mice and Humans (Foster et al. 2020)

https://www.mdpi.com/2079-7737/9/7/180

Exercise mitigates sleep-loss-induced changes in glucose tolerance, mitochondrial function, sarcoplasmic protein synthesis, and diurnal rhythms (Saner et al. 2021)

https://doi.org/10.1016/j.molmet.2020.101110

Prior Exercise Lowers Blood Pressure During Simulated Night-Work With Different Meal Schedules (Fullick et al. 2009)

https://pubmed.ncbi.nlm.nih.gov/19556971/

Impact of the human circadian system, exercise, and their interaction on cardiovascular function (Scheer et al. 2010)

https://www.pnas.org/doi/full/10.1073/pnas.1006749107

Timing of Moderate-to-Vigorous Physical Activity Is Associated with Improvements in Glycemic Control in Type 2 Diabetes in the Look AHEAD Study (Qian et al. 2022)

https://doi.org/10.2337/db22-537-P

Heart attacks are more common in the morning:

Circadian Variation of Ambulatory Myocardial Ischemia: Triggering by Daily Activities and Evidence for an Endogenous Circadian Component (Krantz et al. 1996)

https://doi.org/10.1161/01.CIR.93.7.1364

How to contact Frank Scheer:

LinkedIn: https://www.linkedin.com/in/frankscheer/

Email: FSCHEER@BWH.HARVARD.EDU