The findings have significant public health consequences, particularly for those who live in urban areas, where circadian rhythms are often disrupted due to artificial light, according to Smith. Several media reports included comments by one of the researchers, with the Mail Online advising: "Turn your phone off after 10pm to stay happy". Meanwhile, the findings of the study remained consistent even when controlling factors such as age, gender, education, lifestyle, and body mass index. With the data, circadian relative amplitude, which is a measure of the extent to which circadian rhythmicity of rest-activity cycles is disrupted, was evaluated. "However, these are observational associations and can not tell us whether mood disorders and reduced wellbeing cause disturbed rest-activity patterns, or whether disturbed circadian rhythmicity makes people vulnerable to mood disorders and poorer wellbeing". This information was linked to mental health questionnaires to assess symptoms of mental disorders and subjective wellbeing and cognitive function.
For the latest study, researchers analysed activity data on 91,105 people to measure their daily rest-activity rhythms (also known as relative amplitude). Lower relative amplitude was also found to be reliably associated with greater mood instability, higher neuroticism scores, more subjective loneliness, lower happiness and health satisfaction, and slower reaction time (an indirect measure of cognitive function).
How did the researchers interpret the results?
"Previous studies have identified associations between disrupted circadian rhythms and poor mental health, however, these were on relatively small samples".
The study can not say conclusively that body clock disturbances are what caused the mental risk, instead of the other way round.
Autopsy confirms St. Petersburg man died from vape pen explosion
And in 2016, a vape pen user in NY suffered third-degree burns after the pen exploded in his trousers , NBC 4 NY reported. They include a man losing several teeth and suffering second-degree burns in January 2017 when a vape pen exploded.
They also said the findings "cannot speak to the issue of causal associations" because of its cross-sectional nature, and that future work following up participants is needed.
The big question is exactly how this link works and what "direction" it's travelling in: does poor sleep and sluggish activity during the day affect people's mental health, increasing their chances of mood disorders, or do mood disorders affect people's ability to sleep well and be active during the day?
"It's widely known that a good night's sleep is a good thing for well-being and health".
'Pokemon' game for Nintendo Switch rumored to be announed soon
The reason for Pokemon on Nintendo Switch to take cues from Pokemon Go has to with the tremendous success seen by the latter. The only thing we know for sure is that Game Freak is indeed working on a more traditional Pokemon game for the Switch.
This study had some limitations.
The age group in the study is 37 to 73 and so skewed towards middle-aged and older people, who may be less likely to experience mental health problems for the first time.
"But it's not just what you do at night", he said, "it's what you do during the day - trying to be active during the day and inactive in darkness", he told.
More workers ask for mental health help
Switching off from work was the most popular action (27%), followed by seeking colleague support (26%) and listening to music (13%).
'Especially in the winter, making sure you get out in the morning in the fresh air is just as important in getting a good night's sleep as not being on your mobile phone'.