In the second part with Prof. Christian Cajochen (Head of the Centre for Chronobiology at the University of Basel in Switzerland), contributing to the Daylight Awareness Week (28th of October - 2nd of November 2024), we continue our discussion around the impact of daylight on our health, with a special focus on sleep. Christian summarizes the negative effects of bright electric light exposure on sleep and other health outcomes. On the other hand, he highlights the importance of daylight and alternatively increased electric light intensities during daytime for sleep. We also discuss how seasonal changes in daylight affect us more than we think. Christian gives insights into a real-world example of how switching to dynamic lighting at the workplace changed people’s wellbeing. And lastly, we discuss if a medical pill could eventually replace the health effects of daylight.
More information about the Daylight Awareness Week: https://daylight.academy/daylight-awareness-week-2024/
Chapters:
(0:00:12) Intro & Daylight Awareness Week
(0:00:48) Topics of this episode series
(0:02:13) Introduction to sleep
(0:04:15) Evening electric light & sleep
(0:09:42) Daylight & sleep
(0:15:47) Seasonal effects of daylight
(0:20:33) Can higher light intensities during daytime reduce negative effects of evening light?
(0:25:47) How to tackle the lack of daylight as a society?
(0:36:00) Take-home message on daylight & health
(0:37:39) Christian’s career goals & future research
(0:41:15) Funny anecdotes
(0:47:18) Outro & Teaser to Part 2
Studies that Christian refers to: Evening administration of melatonin and bright light: Interactions on the EEG during sleep and wakefulness
https://doi.org/10.1046/j.1365-2869.1998.00106.x
Blue Blocker Glasses as a Countermeasure for Alerting Effects of Evening Light-Emitting Diode Screen Exposure in Male Teenagers
https://doi.org/10.1016/j.jadohealth.2014.08.002
Evaluating the Association between Artificial Light-at-Night Exposure and Breast and Prostate Cancer Risk in Spain (MCC-Spain Study)
https://doi.org/10.1289/EHP1837
Camping Study: “Circadian Entrainment to the Natural Light-Dark Cycle across Seasons and the Weekend”
Effect of daylight LED on visual comfort, melatonin, mood, waking performance and sleep
https://doi.org/10.1177/1477153519828419
Positive Effect of Daylight Exposure on Nocturnal Urinary Melatonin Excretion in the Elderly: A Cross-Sectional Analysis of the HEIJO-KYO Study
https://doi.org/10.1210/jc.2012-1873
Effect of Bright Light and Melatonin on Cognitive and Noncognitive Function in Elderly Residents of Group Care Facilities: A Randomized Controlled Trial
https://doi.org/10.1001/jama.299.22.2642
Preprint article: “Sex and seasonal variations in melatonin suppression, and alerting response to light”
https://doi.org/10.1101/2024.10.18.619012
Light therapy in non-seasonal depression: An update meta-analysis
https://doi.org/10.1016/j.psychres.2020.113247
Pre-print article: “Afternoon to early evening bright light exposure reduces later melatonin production in adolescents”
https://doi.org/10.1101/2024.10.02.616112
Regular Caffeine Intake Delays REM Sleep Promotion and Attenuates Sleep Quality in Healthy Men
https://doi.org/10.1177/07487304211013995
Evidence that the Lunar Cycle Influences Human Sleep
How to contact Christian Cajochen:
Email: Christian.Cajochen@upk.ch
Twitter: @ollen44
LinkeIn: https://www.linkedin.com/in/christian-cajochen-1435258/
