Night owls can 'retrain' their body clocks to improve mental well-being and performance
June 10, 2019
Science Daily/University of Birmingham
A simple tweak to the sleeping patterns of 'night owls' -- people with extreme late sleeping and waking habits -- could lead to significant improvements in sleep/wake timings, improved performance in the mornings, better eating habits and a decrease in depression and stress.
New international research by the Universities of Birmingham and Surrey in the UK, and Monash University in Australia, showed that, over a three-week period, it was possible to shift the circadian rhythm of 'night owls' using non-pharmacological and practical interventions.
The study, recently published in Sleep Medicine, showed participants were able to bring forward their sleep/wake timings by two hours, while having no negative effect on sleep duration. In addition, participants reported a decrease in feelings of depression and stress, as well as in daytime sleepiness.
"Our research findings highlight the ability of a simple non-pharmacological intervention to phase advance 'night owls', reduce negative elements of mental health and sleepiness, as well as manipulate peak performance times in the real world," lead researcher Dr Elise Facer-Childs from Monash University's Turner Institute for Brain and Mental Health said.
'Night owls' are individuals whose internal body clock dictates later-than-usual sleep and wake times -- in this study participants had an average bedtime of 2.30am and wake-up time of 10.15am.
Disturbances to the sleep/wake system have been linked to a variety of health issues, including mood swings, increased morbidity and mortality rates, and declines in cognitive and physical performance.
"Having a late sleep pattern puts you at odds with the standard societal days, which can lead to a range of adverse outcomes -- from daytime sleepiness to poorer mental wellbeing," study co-author Dr Andrew Bagshaw from the University of Birmingham said.
"We wanted to see if there were simple things people could do at home to solve this issue. This was successful, on average allowing people to get to sleep and wake up around two hours earlier than they were before. Most interestingly, this was also associated with improvements in mental wellbeing and perceived sleepiness, meaning that it was a very positive outcome for the participants. We now need to understand how habitual sleep patterns are related to the brain, how this links with mental wellbeing and whether the interventions lead to long-term changes."
Twenty-two healthy individuals participated in the study. For a period of three weeks participants in the experimental group were asked to:
· Wake up 2-3 hours before regular wake up time and maximise outdoor light during the mornings.
· Go to bed 2-3 hours before habitual bedtime and limit light exposure in the evening.
· Keep sleep/wake times fixed on both work days and free days.
· Have breakfast as soon as possible after waking up, eat lunch at the same time each day, and refrain from eating dinner after 7pm.
The results highlighted an increase in cognitive (reaction time) and physical (grip strength) performance during the morning when tiredness is often very high in 'night owls', as well as a shift in peak performance times from evening to afternoon. It also increased the number of days in which breakfast was consumed and led to better mental well-being, with participants reporting a decrease in feelings of stress and depression.
"Establishing simple routines could help 'night owls' adjust their body clocks and improve their overall physical and mental health. Insufficient levels of sleep and circadian misalignment can disrupt many bodily processes putting us at increased risk of cardiovascular disease, cancer and diabetes," Professor Debra Skene from the University of Surrey said.
Dr Facer-Childs said 'night owls', compared to 'morning larks', tended to be more compromised in our society due to having to fit to work/school schedules that are out of sync with their preferred patterns.
"By acknowledging these differences and providing tools to improve outcomes we can go a long way in a society that is under constant pressure to achieve optimal productivity and performance," she said.
This intervention could also be applied within more niche settings, such as industry or within sporting sectors, which have a key focus on developing strategies to maximise productivity and optimise performance at certain times and in different conditions.
https://www.sciencedaily.com/releases/2019/06/190610100622.htm
Night owls have higher risk of dying sooner
Evening types have 10 percent higher risk of dying than morning counterparts
April 12, 2018
Science Daily/Northwestern University
Night owls -- people who prefer to stay up late and sleep late -- have 10 percent higher risk of dying sooner than larks, people who go to bed early and rise early, reports a new study. This is the first study to show 'owls' have higher risk of mortality. Owls also suffer from more diseases and disorders than morning larks. Employers should allow greater flexibility in working hours for owls, scientists said.
The study, on nearly half a million participants in the UK Biobank Study, found owls have a 10 percent higher risk of dying than larks. In the study sample, 50,000 people were more likely to die in the 6½ -year period sampled.
"Night owls trying to live in a morning lark world may have health consequences for their bodies," said co-lead author Kristen Knutson, associate professor of neurology at Northwestern University Feinberg School of Medicine.
Previous studies in this field have focused on the higher rates of metabolic dysfunction and cardiovascular disease, but this is the first to look at mortality risk.
The study will be published April 12 in the journal Chronobiology International.
The scientists adjusted for the expected health problems in owls and still found the 10 percent higher risk of death.
"This is a public health issue that can no longer be ignored," said Malcolm von Schantz, a professor of chronobiology at the University of Surrey. "We should discuss allowing evening types to start and finish work later, where practical. And we need more research about how we can help evening types cope with the higher effort of keeping their body clock in synchrony with sun time."
"It could be that people who are up late have an internal biological clock that doesn't match their external environment," Knutson said. "It could be psychological stress, eating at the wrong time for their body, not exercising enough, not sleeping enough, being awake at night by yourself, maybe drug or alcohol use. There are a whole variety of unhealthy behaviors related to being up late in the dark by yourself."
In the new study, scientists found owls had higher rates of diabetes, psychological disorders and neurological disorders?
Can owls become larks?
Genetics and environment play approximately equal roles in whether we are a morning or a night type, or somewhere in between, the authors have previously reported.
"You're not doomed," Knutson said. "Part of it you don't have any control over and part of it you might."
One way to shift your behavior is to make sure you are exposed to light early in the morning but not at night, Knutson said. Try to keep a regular bedtime and not let yourself drift to later bedtimes. Be regimented about adopting healthy lifestyle behaviors and recognize the timing of when you sleep matters. Do things earlier and be less of an evening person as much as you can.
Society can help, too
"If we can recognize these chronotypes are, in part, genetically determined and not just a character flaw, jobs and work hours could have more flexibility for owls," Knutson said. "They shouldn't be forced to get up for an 8 a.m. shift. Make work shifts match peoples' chronotypes. Some people may be better suited to night shifts."
In future research, Knutson and colleagues want to test an intervention with owls to get them to shift their body clocks to adapt to an earlier schedule. "Then we'll see if we get improvements in blood pressure and overall health," she said.
The switch to daylight savings or summer time is already known to be much more difficult for evening types than for morning types.
"There are already reports of higher incidence of heart attacks following the switch to summer time," says von Schantz. "And we have to remember that even a small additional risk is multiplied by more than 1.3 billion people who experience this shift every year. I think we need to seriously consider whether the suggested benefits outweigh these risks."
How the study worked
For the study, researchers from the University of Surrey and Northwestern University examined the link between an individual's natural inclination toward mornings or evenings and their risk of mortality. They asked 433,268 participants, age 38 to 73 years, if they are a "definite morning type" a "moderate morning type" a "moderate evening type" or a "definite evening type." Deaths in the sample were tracked up to six and half years later.
The study was supported by the University of Surrey Institute?of Advanced Studies Santander fellowship and the National Institute of Diabetes and Digestive and Kidney Diseases grant R01DK095207 from the National Institutes of Health.
https://www.sciencedaily.com/releases/2018/04/180412085736.htm