When it’s smart to be in the dark

When Willie Nelson croons, “Turn out the lights/the party’s over/They say all good things must end,” he’s not quite right, as far as your health is concerned. That’s because turning off the lights at night is essential for good physical and mental health – and not just for you, but perhaps for your kids-to-be!

Research has shown that sleeping in a dimly lit instead of dark environment is associated with disruption of circadian rhythm (your internal body clock) and neuroendocrine physiology (how your nerves and hormones work together). This can trigger insomnia (related to mood shifts and weight gain) and accelerate tumor growth.

One Israeli study even found that women living in neighbourhoods where it was bright enough to read a book outside at midnight had a 73 per cent higher risk of developing breast cancer than those who lived in areas with the least outdoor artificial light.

And now researchers have found that the health disruption from light pollution might get passed down through generations. A recent lab study found that when hamsters are exposed to an unnatural mix of daylight and darkness, it can cause epigenetic changes that alter both male and female biochemistry. Then, when they mate, their offspring end up with weakened immune systems and impaired endocrine activity.

Our advice: Shut off the TV and digital devices when you turn off the lights; buy blackout curtains/blinds to keep ambient light out of bedrooms; use only red-wavelength light in your bathroom; wear a sleep mask; and say a healthy “goodnight” to the Willie Nelson tunes!