Waking up just an hour earlier could reduce the risk of depression by 23 percent, a new genetic study reveals.
Researchers at the University of Colorado Boulder analyzed the genetic data of nearly 840,000 adults of European descent.
They found a link between earlier sleep patterns — getting up early and going to bed — and a lower risk of “major depressive disorder.”
It is possible that the increased exposure to light during the day results in ‘a cascade of hormonal effects’ that can affect mood.
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The study suggests that people suffering from depression would benefit from getting up just an hour earlier (stock image)
RECOMMENDED SLEEP DURATION
– Toddler (3-5 years): 10-13 hours
– School age (6-13 years): 9-11 o’clock
– Teenager (14-17 years): 8-10 hours
– young adult (18-25) 7-9 hours
– Grown up (26-64): 7-9 hours
– Older Adult (65 or more) 7-8 hours
Source: Sleep Foundation
“We’ve known for a while that there’s a link between sleep timing and mood,” said study co-author Celine Vetter, an assistant professor of integrative physiology at CU Boulder.
“But one question we often hear from clinicians is, ‘How much sooner do we have to move people to see a benefit?”
“We found that even an hour earlier sleep timing is associated with a significantly lower risk of depression.”
For those who want to shift themselves to an earlier sleep schedule, Vetter says, “Keep your days bright and your nights dark.
“Have your morning coffee on the porch. Walk or cycle to work if you can and dim those electronics in the evening.’
For their research, the team focused on genetics, which together explain anywhere from 12 to 42 percent of our sleep timing preferences, they say.
Using data from DNA testing company 23 and Me and the UK Biobank biomedical database, the researchers assessed anonymized genetic data on these variants of the 840,000 adults.
This total included data from 85,000 people who wore wearable sleep trackers for seven days and 250,000 who completed sleep preference questionnaires.
In the largest of these samples, one-third of the subjects surveyed identified themselves as morning larks (someone who goes to bed early and gets up early) and nine percent as night owls (goes to bed and gets up late). The rest were somewhere in the middle.
In general, the average sleep center was 3 a.m., meaning they went to bed at 11 p.m. and got up at 6 a.m.
Researchers then looked at genetic information along with anonymized medical and prescription data and surveys on major depressive disorder diagnoses.
It is possible that the increased light exposure during the day results in ‘a cascade of hormonal effects’ that can affect mood (stock image)
Less than five hours of sleep per night may DOUBLE your risk of developing dementia, study warns
Five hours or less of sleep a night doubles the risk of dementia, a new study warns.
Researchers at Brigham and Women’s Hospital in Boston looked at data from 2,812 American adults ages 65 and older.
“Very short” sleep duration, defined as five hours or less, doubled the risk of dementia compared to the “recommended” duration of seven to eight hours, they found.
The study supports previous research that lack of sleep essentially ‘sets the stage’ for forms of dementia such as Alzheimer’s disease.
While this study didn’t look at the reason behind the link, it’s possible that a lack of proper rest prevents the brain from clearing the toxins that cause ongoing decline in brain function.
The individuals with genetic variants that predisposed them to be early risers also had a lower risk of depression, the team found.
Each one hour earlier sleep midpoint (halfway between bedtime and wake time) corresponded to a 23 percent lower risk of major depressive disorder.
This suggests that if someone who normally goes to bed at 1 a.m. instead goes to bed at midnight and sleeps at the same time, they could reduce their risk by 23 percent.
If they went to bed at 11 p.m., they could reduce depression risk even more — by about 40 percent.
It is unclear from the study whether those who get up early can benefit from getting up even earlier.
But for those in the intermediate range or “night owl” range, moving to an earlier bedtime would probably be helpful.
The team used “Mendelian randomization” for their study – an epidemiological technique that uses genetic differences to distinguish a simple correlation from causation (one factor directly causes another).
“Our genetics are determined at birth, so some biases that influence other types of epidemiological research usually don’t affect genetic studies,” said lead study author Iyas Daghlas of Harvard University.
“This study definitely shifts the weight of evidence to support a causal effect of sleep timing on depression.”
Previous research has provided a better understanding of the circadian rhythm, or “clock,” which regulates exactly when we become sleepy and when we are more alert.
One of the proteins crucial for determining the timing of the clock, as well as the timing of sleep, is Period2 or PER2.
PER2 is a mammalian protein encoded by the PER2 gene.
More than 340 common genetic variants, including variants in the so-called “clock gene” PER2, are known to influence a person’s chronotype — a tendency to sleep at a specific time.
The research team believes theirs is some of the strongest evidence that chronotype influences depression risk.
A large randomized clinical trial is needed to definitively determine whether going to bed early can reduce depression, Daghlas added.
The study is published in the journal JAMA Psychiatry.
What is depression?
While it’s normal to feel down from time to time, people with depression can feel persistently unhappy for weeks or months.
Depression can affect anyone at any age and is quite common – about one in ten people are likely to experience it at some point in their lives.
Depression is a real health condition that people can’t just ignore or ‘get out’.
Symptoms and effects vary, but may include feeling constantly upset, hopeless, or losing interest in things you used to enjoy.
It can also cause physical symptoms, such as trouble sleeping, fatigue, a low appetite or sex drive, and even physical pain.
In extreme cases, it can lead to suicidal thoughts.
Traumatic events can cause it, and people with a family history may be more at risk.
It’s important to see a doctor if you think you or someone you know has depression, as it can be treated with lifestyle changes, therapy, or medication.
Source: NHS Choices