GOOD sleep is key to warding off the blues, scientists say.
A University College London study found that regularly sleeping less than five hours a night can raise the risk of depression.
Consistently sleeping less than five hours a night has been linked to a higher risk of depression
Experts thought bad sleep was a symptom of poor mental health but say the opposite is also true.
Dr Odessa Hamilton said: “We determined that short sleep likely precedes depressive symptoms, rather than the other way around.”
It’s thought that a third of Brits will experience sleep issues in their lifetime, while one in four will experience mental health problems like depression, according to charity Mind.
UCL researchers used genetic and health data from 7,146 people in England and pinpointed genetic variants showing if participants were prone to depression or short sleep.
People who snoozed less because of their genes were more likely to feel down or lonely over the next four to 12 years.
But people at higher risk of depression weren’t more likely to sleep less.
Participants who didn’t have a tendency for short kip because of their genes were still more than twice as likely to get depression if they often slept five hours or less each night.
Meanwhile, those with depression were a third more likely to get little sleep.
Published in Translational Psychiatry, the study also found a link between sleeping too long and feeling blue.
People slumbering longer than nine hours were 1.5 times more likely to have depression than those getting seven hours of sleep.
Study participants – who had an average age of 65 – got about seven hours’ sleep a night. The NHS recommends having between seven and nine.
About 10 per cent snoozed less than five hours nightly at the start of the research, rising to 15 per cent by the end.
Those suffering from depression rose from 8.75 to 11.5 per cent.
Professor Andrew Steptoe said: “Poor sleep and depression increase with age, and with the population ageing worldwide there is a growing need to better understand the connection between depression and a lack of sleep.”
Earlier research has shown that sleep duration and depression are both partly passed down from one generation to the next.
It’s suggested depression is about 35 per cent inherited, while genes account for 40 per cent of the variance in sleep duration.
How can I tell if I’m depressed?
Symptoms of depression can vary from person to person, according to mental health charity Mind, as can how intense they are and how long they last.
You might feel:
Down, upset or tearfulRestless, agitated or irritableGuilty, worthless and down on yourselfEmpty and numbIsolated and unable to relate to other peopleFinding no pleasure in life or things you usually enjoyAngry or frustrated over minor thingsA sense of unrealityNo self-confidence or self-esteemHopeless and despairingFeeling tired all the time
Feeling this way can also make you start acting differently or withdrawing from things that usually bring you pleasure.
You might:
Avoid social events and activities you usually enjoyHave suicidal thoughts and self harm have difficulty speaking, thinking clearly or making decisionsLose interest in sexHave difficulty remembering or concentrating on thingsUse more tobacco, alcohol or other drugs than usualHave trouble sleeping, or sleep too muchHave no appetite and lose weight, or eat more than usual and gain weightExperience physical aches and pains with no obvious physical causeFeel restless and agitated
If you think you might be depressed, it’s worth speaking to someone you trust about how you’re feeling.
But if you don’t feel like you can open up to someone close to you, you can call a helpline and speak to someone confidentially.
You can call Samaritans any time on 116 123.
Sane has an online forum where you can read about other people’s experiences with depression or write about your own.
Or Depression UK has a penfriend scheme for members.
You can also visit the Mind website for information about support groups in your area.