A new study found that if you sleep with any type of light in the room with you, it’s shown that it can raise your blood sugar and your heart rate of healthy, young people. The dim light could still shine through the eyelids, disrupting the sleep. When you are sleeping, your heart rate drops. While your heart is slowing down, the brain is repairing and rejuvenating the body for the next day. If you have an elevated heart rate at night, you are now a risk factor for a future heart disease and an early death. Prior research also shows a connection between light at night and weight gain due to disruptions of metabolic function, insulin secretion and then the development of diabetes. All of these health risks can lead to cardiovascular problems.