Unhappy or worried? One reason may be how you sleep

Sign up for CNN’s Sleep, But Better newsletter series. Our seven-part guide has helpful tips for achieving better sleep.

CNN
—

did not receive Not getting enough sleep or sleeping poorly It can affect you greatly Mood and mental healthA new study analyzes 50 years of research.

“We found that all types of sleep loss — total sleep loss, partial sleep loss, and sleep fragmentation — resulted in emotional changes. The strongest and most consistent effect was that sleep loss reduced positive mood,” said Dr. Cara Palmer said.

“We found that sleep deprivation increased feelings of anxiety,” Palmer said in an email. “When experiencing emotional events, people are more likely to report behaving differently than well-rested people.

“Specifically, they felt less emotional arousal, which is when our body perceives the intensity of certain emotions, and overall people reported feeling more emotional reactions after sleep deprivation.”

Adults over the age of 18 need at least seven hours of solid sleep a night to stay healthy. According to the US Centers for Disease Control and Prevention. Below that minimum, the numbers can be steep: Studies have linked them to poor sleep Obesity increases risk of heart disease And Dementiaas well as Mood disorders.

Despite the dangers, More than 30% are adults Get a daily sleep credit – when you sleep less than your body needs – by more than an hour, 1 in 10 adults lose two or more hours of sleep each night. 2022 study detected.

“Worldwide, individuals rarely get the recommended amount of sleep for at least 5 nights per week,” Joe Bower, a lecturer at the University of East Anglia in Norwich, England, said in an email. “Our work shows the potential consequences for our emotional health at a time when mental health problems are rapidly increasing.”

Published on Thursday Psychological Bulletin, a journal of the American Psychological Association, analyzed data from 154 studies of more than 5,000 people over five decades.

In those studies, researchers disrupted participants’ sleep for one or more nights, causing them to wake up (insomnia), wake up periodically (sleep deprivation), or wake up earlier than usual (partial sleep deprivation). Afterwards, participants were tested for anxiety, depression, mood and their response to emotional stimuli.

“In general, total sleep deprivation had a greater impact on mood and emotions compared to partial sleep loss or fragmented sleep,” Palmer said. “Interestingly, the effect of sleep on positive mood persisted afterward Short term sleep lossWaking up an hour or two later than usual or after losing a few hours of sleep.”

A “large and comprehensive” meta-analysis emphasizes strong links between mental health and sleep, said sleep specialist and pulmonologist Dr. Raj Dasgupta said. Professor of Clinical Medicine, Keck School of Medicine, University of Southern California. He is not involved in research.

“Perhaps there is truth behind this saying: ‘Woke up on the wrong side of the bed,’” Dasgupta said in an email. “Studies included in the meta-analysis found that people with poor quantity and quality of sleep felt more stressed, angry, sad, and mentally exhausted. When subjects resumed normal sleep, they reported dramatic improvements in mood.

What is sleep that makes our bodies function like this? The answers are in the brain, Palmer said.

“We know from previous research that sleep loss affects the neural circuits involved in experiencing reward or positive experiences, which plays a role,” he said. “We also see heightened responses in areas of the brain involved in experiences of emotion. …

“At the same time, the connections between our brain’s emotional centers and our prefrontal cortex, which helps us appropriately control our emotional reactions, are weakened.”

Although all types of sleep deprivation affect mood, the study found that reactions to emotional experiences were more negative after loss Rapid eye movement (REM) sleep When compared to losing slow wave or “deep” sleep.

when Slow sleepThe body removes potentially harmful substances from the brain — including beta-amyloid protein, a hallmark of Alzheimer’s disease.

“Both can be important, but in different ways,” Bower said. “For example, previous work has shown that REM sleep can be linked to the processing of emotional memories and affect mood through cognitive processes.”

However, slow-wave sleep can be linked to the brain’s reward centers, which can affect responses to positive emotional situations, he said.

Deep sleep is considered one of the best markers of sleep quality because a person must have relatively uninterrupted sleep to achieve it. Since each sleep cycle is approximately 90 minutes long, most adults need seven to eight hours of uninterrupted sleep to achieve restorative sleep. CDC.

Impact on anxiety and depression

Lack of sleep also worsens symptoms Anxiety and depressionEven in people with no known mental or physical health conditions, according to the study.

“Extended periods of wakefulness caused more severe depression or anxiety symptoms,” Palmer said. “Sleep loss may affect people who are already depressed or who have genetic risk differences for depression. For example, some of our previous work suggests that people who are already anxious may experience exaggerated responses to sleep deprivation.

Difficulty sleeping can be one of the first signs of a developing mental disorder, Dasgupta said.

“Chronic sleep deprivation can increase a person’s risk of developing mood disorders such as depression or anxiety,” he said. “Insomnia may be an even greater risk factor for anxiety. The studies included in the meta-analysis show that individuals with insomnia are more likely to develop an anxiety disorder and that insomnia is a reliable predictor of depression.

Obstructive sleep apnea, in which the body may stop breathing for 10 seconds or more at a time, can create fragmented and chaotic sleep, Dasgupta said. This type of sleep disorder “occurs frequently in people with mental health conditions and should be addressed,” he said.

More research is needed to determine the impact of poor sleep on people with pre-existing psychiatric disorders. Adolescents and childrenBut each person should be careful to prioritize sleep in their lives, Bower said.

“Allowing yourself time to sleep is an important step in self-care, as is eating well and exercising,” Bower said. “It’s also important that we make systemic changes that support individuals’ ability to get good quality sleep.”

“This includes considering policies related to school start times, work hours, shift patterns and access to health care that supports treatment for sleep problems.”