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The
are from the Northwestern University Feinberg School of Medicine in Chicago, USA. The
researcher, Dr Phyllis Zee, is an
in sleep medicine. She said it is healthier for us to turn off all lights when we sleep. Her
conducted a study of the blood
levels of 20 people after nights of sleep. The people who slept with a light on had
blood sugar levels the next morning compared to those who slept in
darkness. Dr Zee said this is because light stimulates brain activity, which raises blood sugar levels. She said there are three things we can do to reduce the
of illness: turn off the lights,
sleep with white or blue light; and use a blackout curtain or wear an eye
.