Waking up one hour earlier can reduce the risk of depression by almost a quarter, research has found.
The large-scale study explored how much, or how little, change is needed to a person’s sleep pattern to influence their mental health.
The survey of 840,000 people found that waking just 60 minutes earlier in the morning can cut the risk of developing major depression by 23%.
Researchers at University of Colorado Boulder and the Broad Institute of MIT and Harvard wanted to examine just how beneficial shifting a person’s sleep pattern can be – and the results could have important implications.
Senior author Celine Vetter, assistant professor of integrative physiology at CU Boulder, said: “We have known for some time that there is a relationship between sleep timing and mood, but a question we often hear from clinicians is: How much earlier do we need to shift people to see a benefit?
“We found that even one-hour earlier sleep timing is associated with significantly lower risk of depression.”
Vetter has previously studied the sleep patterns of 32,000 nurses and found that early risers were up to 27% less likely to suffer from depression over the course of four years. The findings led to the question, what makes an early riser?
Genetics explain between 12 and 42% of a person’s chronotype – their tendency to sleep at certain times.
Researchers used new techniques to look at whether people with certain genetic variants which cause them to get up early also have a lower risk of developing depression.
They found that when someone who usually goes to sleep at 1am goes to bed an hour earlier – and sleeps for the same amount of time – they reduce their risk of depression by 23%. If they are asleep by 11pm, their risk is reduced by around 40%.
Studies have suggested that increasing your light exposure, which early risers benefit from, can have an impact on hormones and mood.
Vetter advises: “Keep your days bright and your nights dark. Have your morning coffee on the porch. Walk or ride your bike to work if you can, and dim those electronics in the evening.”
The study has been published in the journal JAMA Psychiatry.