Try to sleep in complete darkness, as the researchers urge. This will help protect against hypertension, diabetes and even obesity.
The study divided people into two groups. One group was forced to sleep in complete darkness, while the other was exposed to some kind of light in their sleep. Based on the results, the experts concluded that the body's circadian rhythms are very important, and their disruption can lead to poor overall health, especially in the elderly. Poor sleep due to bright light can throw off circadian rhythms. Light at night can impair health by deregulating circadian rhythms, which are vital for disease prevention and optimal performance.
When you sleep, the body produces the hormone melatonin. It has several useful properties. It is an antioxidant and anti-inflammatory agent. If you sleep with the lights on, melatonin secretion will decrease. A person may also experience nightmares, which are caused by unnecessary lighting. In general, sleeping in a lit room increases the risks of:
Obesity
Diabetes
Hypertension
Cardiovascular disease
Metabolic disease
Doctors recommend brushing teeth in the dark
Stress
Sleep in the dark protects against cancer and obesity
Do not turn on the light in the bedroom. If you can't sleep without it, dim the light close to the floor. The color of the light is also important. Amber or red/orange light stimulates the brain less. Do not use white or blue light. If you can't control outdoor lighting, use blackout curtains or wear an eye mask. Position your bed so that outside light does not shine directly into your face. (READ NEXT) 
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