Out of the Lab and into the Bathroom: Evening Short-Term Exposure to Conventional Light Suppresses Melatonin and Increases Alertness Perception

International Journal of Molecular Sciences

Amely Wahnschaffe³  Sven Haedel³  Andrea Rodenbeck³  Claudia Stoll³  Horst Rudolph²  Ruslan Kozakov¹  Heinz Schoepp¹ 

[1] Leibniz Institute for Plasma Science and Technology (INP), 17489 Greifswald, Germany; E-Mails:;Trilux GmbH & Co.KG, 59759 Arnsberg, Germany; E-Mail:;Institute of Physiology, Charité–Universitätsmedizin Berlin (CBF), 10115 Berlin, Germany; E-Mails:

关键词: melatonin;    circadian rhythm;    light;    sleep disturbances;    alertness;   

DOI  :  10.3390/ijms14022573

来源: mdpi

【 摘 要 】

Life in 24-h society relies on the use of artificial light at night that might disrupt synchronization of the endogenous circadian timing system to the solar day. This could have a negative impact on sleep–wake patterns and psychiatric symptoms. The aim of the study was to investigate the influence of evening light emitted by domestic and work place lamps in a naturalistic setting on melatonin levels and alertness in humans. Healthy subjects (6 male, 3 female, 22–33 years) were exposed to constant dim light (<10 lx) for six evenings from 7:00 p.m. to midnight. On evenings 2 through 6, 1 h before habitual bedtime, they were also exposed to light emitted by 5 different conventional lamps for 30 min. Exposure to yellow light did not alter the increase of melatonin in saliva compared to dim light baseline during (38 ± 27 pg/mL vs. 39 ± 23 pg/mL) and after light exposure (39 ± 22 pg/mL vs. 44 ± 26 pg/mL). In contrast, lighting conditions including blue components reduced melatonin increase significantly both during (office daylight white: 25 ± 16 pg/mL, bathroom daylight white: 24 ± 10 pg/mL, Planon warm white: 26 ± 14 pg/mL, hall daylight white: 22 ± 14 pg/mL) and after light exposure (office daylight white: 25 ± 15 pg/mL, bathroom daylight white: 23 ± 9 pg/mL, Planon warm white: 24 ± 13 pg/mL, hall daylight white: 22 ± 26 pg/mL). Subjective alertness was significantly increased after exposure to three of the lighting conditions which included blue spectral components in their spectra. Evening exposure to conventional lamps in an everyday setting influences melatonin excretion and alertness perception within 30 min.

【 授权许可】

CC BY   
© 2013 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.