Nighttime light exposure: 3 lux in the bedroom thicken the heart wall https://www.forschung-und-wissen.de/nachrichten/medizin/drei-lux-im-schlafzimmer-verdicken-die-herzwand-133712848 3 lux roughly corresponds to the brightness of a mobile phone display on a low setting, the light from a digital alarm clock display, or the light spilling into a room from an illuminated hallway through a slightly ajar door! There are links between nighttime lighting and the occurrence of stroke and atrial fibrillation. Nighttime light exposure and cardiac structure and function https://academic.oup.com/eurheartj/advance-article/doi/10.1093/eurheartj/ehag563/8770409