Sleeping with the lights on overnight increases the risk of heart disease and diabetes

Everyone should have had the experience of sleeping with the lights on for various reasons, such as being not good at being pitch black when sleeping or falling asleep due to fatigue. Studies have suggested that such 'bathing in the light at bedtime' may cause an increase in heart rate and increase the risk of heart disease and diabetes.

Light exposure during sleep impairs cardiometabolic function | PNAS

Even moderate light exposure can harm your health, study finds | PhillyVoice

Ivy Mason and colleagues at Northwestern University conducted an experiment in which 20 young subjects were asked to sleep in either 'medium light' or 'dim light' indoor environments. The amount of light in the former is 100 lux, which is generally the brightness when the interior lights are fully lit. The latter has a light intensity of 3 lux, which is darker than candlelight and slightly brighter than moonlight.

When asked to sleep overnight in each indoor environment, those who slept in moderate light showed higher heart rate and blood glucose levels than those who slept in dim light, and the effect was commensurate with the concentration. It was shown that insulin resistance was not exhibited.

We also found that although there was no difference in sleep quality reported by subjects in both groups, the proportion of REM sleep was lower in those who slept in moderate light. Mason and colleagues say that leaving the lamp on during sleep even overnight can increase your risk of heart disease and diabetes.

'It's important to keep out of the light or minimize the light during sleep,' said Philis Lee of Northwestern University. 'Mute the TV and leave it on, or a bright lamp at the bedside. Putting on can also cause heart disease and diabetes. Dimm the lights at least an hour before bedtime. '

in Science, Posted by log1p_kr