TURN THE LIGHT OFF!

Exposure to even moderate ambient lighting during night-time sleep, compared to sleeping in a dimly lit room, harms your cardiovascular function during sleep and increases your insulin resistance the following morning, reports a new study from Northwestern University. “The results from this study demonstrate that just a single night of exposure to moderate room lighting during sleep can impair glucose and cardiovascular regulation, which are risk factors for heart disease, diabetes and metabolic syndrome,” said senior study author Dr Phyllis Zee. “It’s important for people to avoid or minimise the amount of light exposure during sleep.” The study showed heart rate increases when you sleep in a moderately lit room because your brain still senses the light even though you are asleep. “Even though you are asleep, your autonomic nervous system is activated,” says Dr Zee. “That’s bad. Usually, your heart rate, together with other cardiovascular parameters are lower at night and higher during the day. If you’re able to see things really well, it’s probably too light.”

Her top tips for reducing light during sleep include:

1 Don’t turn lights on. If you need to have a light on (which older adults may want for safety), make it a dim light that is closer to the floor.

2 Colour is important. Amber or a red/orange light is less stimulating for the brain. Don’t use white or blue light and try to keep it far away from the sleeping person.

3 Blackout shades or eye masks are good if you can’t control the outdoor light. Move your bed so the outdoor light is not shining on your face.