Research shows that sleeping less than 5 hours may increase your risk of developing symptoms of depression.

The relationship between sleep deprivation and mental illness is well known, but it is unclear which problems tend to appear first. Now, scientists have found evidence that short periods of nightly sleep may be a precursor to developing symptoms of depression.

"There is a chicken-and-egg scenario between suboptimal sleep duration and depression. They often occur together, but which comes first is largely unknown. Not. "Taking advantage of genetic susceptibility to disease, we found that sleep is more likely to precede symptoms of depression, rather than the other way around," said UCL PhD student and lead author of the study. Odessa Hamilton said.

Researchers looked at genetic and health data from 7,146 people recruited as part of the UK Longitudinal Study of Aging (ELSA). Sleep duration and depression are both partially genetic. Previous research has shown that depression is approximately 35% heritable and that 40% of variance in sleep duration is due to genetic differences.

After following the participants in this study over time, researchers found that people with a genetic predisposition to short sleep duration (less than 5 hours per night) experienced symptoms of depression over a period of 4 to 12 years. They found that, although likely, this did not mean that people predisposed to depression were genetically more likely to suffer from sleep disorders.

Overall, study participants slept an average of 7 hours per night. At the beginning of the study period, more than 10% slept less than 5 hours a night; by the end of the study period, this number rose to more than 15%, and the proportion of participants with depressive symptoms went from approximately 9% to 11%. Increased.

People who sleep less than 5 hours are 2.5 times more likely to develop symptoms of depression, while people with symptoms of depression are 3 times more likely to suffer from sleep deprivation. It was 1.

The findings could portend a bleak outlook for people already suffering from sleep problems. However, Hamilton said sleep deprivation and depression should not be seen as inevitable outcomes, and the findings highlight the importance of sleep for good mental health.

"My advice is to prioritize sleep and avoid procrastinating it. There is a popular saying in genetics: 'Genes load the gun, environment pulls the trigger.' Although you may be genetically predisposed to it, you can take steps to reduce your risk. ”