Sunny days key to better sleep

Melbourne researchers have found a lack of natural sunlight is affecting people’s mood and sleep quality.

A lack of daylight exposure is considered a risk factor for depression, poor mood and insomnia, the research found. Picture: Damian Shaw

A new study led by researchers at Monash University has revealed getting enough natural sunlight each day can have a big impact on a person’s mood and sleep quality.

The study of more than 400,000 participants in the UK Biobank program found that a lack of daylight exposure was a risk factor for depression, poor mood and insomnia.

Monash University Turner Institute for Brain and Mental Health PhD student Angus Burns and Associate Professor Sean Cain led an international research team that analysed data from the study.

Mr Burns said most health advice about light exposure is focused on avoiding artificial light at night as it disrupts our body clocks whereas this research highlighted the importance of getting enough daylight to ensure our bodies function optimally.

Vikashni Moyle with son, Fox, 3. The Melbourne mum says she notices a big difference in her mood after spending time gardening outside. Picture: Mark Stewart

“In this study, we observed that the greater time spent in outdoor light during the day was associated with fewer depressive symptoms, lower odds of using antidepressant medication, better sleep and fewer symptoms of insomnia,” Mr Burns said.

“These results may be explained by the impacts of light on the circadian system and the direct effects of light on mood centres in the brain.”

Associate Professor Cain said making minor adjustments to a person’s daily routine could help improve their mood, sleep, and energy levels.

“In this study, we observed that greater time spent in outdoor light was associated with better mood outcomes, better quality sleep, and ease of wakening,” he said.

“Insufficient exposure to daytime light could be a key factor contributing to poor mood and sleep outcomes in depressive disorders. My general advice for everyone is simple: when the sun is out, get as much light as you can, but after it sets, keep it dark. Your body will thank you.”

Melbourne mum Vikashni Moyle said she noticed a big difference in her mood after spending time gardening outside with her children which she’d taken up as a hobby during lockdown.

“I’ve never been a garden person, the yard’s always been an overgrown mess but because we’re in lockdown I thought about creating a little garden out the front of my house with my toddler,” she said.

“On really nice warm days out in the sun it’s quite relaxing.”

The mother of two previously lived in Tasmania where she had to take vitamin D supplements to make up for a lack of sunshine.

“Coming from a cooler climate I definitely didn’t get as much [sunlight] and that did affect my mood,” she said.

“Melbourne might get four seasons in one day but at least in Bayside we don’t get a frost which is just a godsend.”

Originally published as Sunny days key to better sleep