MORTEN HALMØ PETERSEN used to live in a windowless basement flat in Copenhagen. If he didn’t get out in the daytime, he would lose track of time and start becoming irritated and depressed. “When you are living in a basement with only artificial light, it becomes very clear that something is lacking,” he says. “It’s an emotional, physical and mental thing all combined.”
You can say that again. Our lifestyles have rapidly changed our relationship with light. Prior to the invention of gas lighting at the turn of the 19th century, the only artificial light we could rely on was from flickering firelight, candles or whale-oil lamps. People also spent many more of their waking hours outside.
Today, the average Westerner spends 90 per cent of their life indoors. That means we are getting less light during the day and being exposed to more light at night. This pattern is increasingly being linked to disrupted sleep and circadian rhythms – 24-hour fluctuations in our biology and behaviour – with consequences for our physical and mental health. Meanwhile, getting too little sunlight is contributing to vitamin D deficiency and may be undermining our immune and cardiovascular systems as well.
Our changed relationship with the sun is profoundly affecting our biology. That’s why people like Petersen are being recruited by researchers to help investigate how much damage we do by shying away from the light, and just how much light we need. The good news is researchers are finding that even small increases in your exposure to bright light …
https://www.newscientist.com/article/mg24232320-100-how-getting-more-daylight-can-improve-your-mental-and-physical-health/