The amount of sleep you should be aiming for each night to avoid increased risk of chronic ailments

Exhausted woman asleep on her desk
The study examined whether sleep duration is associated with incidence of a first chronic disease, subsequent multi-morbidity and mortality using data spanning 25 years. Photo credit: Getty Images

At least five hours of shut-eye per night should reduce the risk of developing multiple chronic health issues in those aged 50 and over, researchers have found. 

The average human spends about 26 years sleeping in their life, which equates to 9490 days or 227,760 hours. Surprisingly, we also spend seven years trying to get to sleep - that's 33 years or 12,045 days spent in bed.

A new study, published in PLoS Medicine on Thursday, tracked the health and sleep of more than 10,000 civil servants in the UK. The participants were asked how many hours of sleep they had on an average weeknight, with the response categories being five hours or less, six hours, seven hours, eights hours, and nine or more hours. The participants were also checked for chronic health conditions including diabetes, cancer and heart disease.

Using data obtained over 25 years of follow-up, the researchers - from University College London and Paris Cité University - found those who slept five hours or less around the age of 50 increased their risk of developing multiple ailments by 30 percent, compared to those who slept seven hours.

Less sleep at 50 was also associated with a higher risk of mortality throughout the study, mainly linked to the increased risk of chronic disease.

"In this study, we observed short sleep duration to be associated with risk of chronic disease and subsequent multimorbidity but not with progression to death," the authors concluded.

"There was no robust evidence of an increased risk of chronic disease among those with long sleep duration at age 50. Our findings suggest an association between short sleep duration and multimorbidity.

"In conclusions, findings from the present study suggest short sleep duration in midlife and old age is associated with higher risk of onset of chronic disease and multimorbidity. These findings support the promotion of good sleep hygiene in both primary and secondary prevention by targeting behavioral and environmental conditions that affect sleep duration and quality."

Experts generally recommend seven to eight hours of shut-eye each night, the researchers noted. 

Speaking to BBC News, Surrey Sleep Centre director Professor Derk-Jan Dijk noted the research reinforces to sleep experts that short periods of shut-eye are not good for our wellbeing.

"Generally, it's not healthy - although for some, it may be OK," he told the outlet.

"The big question is why do some people sleep less. What is causing it and is there anything we can do about it? Sleep is a modifiable lifestyle factor to a certain extent."

Speaking to Newshub last year, Dr Ann Shivas, an expert with a PhD in human nutrition and background in biology, osteopathy and traditional Chinese medicine, shared her top tips for improving your quality of sleep.

Among her advice, Dr Shivas suggested stopping eating two to three hours before bed; improving your day-to-day diet and nutrition; avoiding toxins like alcohol and caffeine before bed; use supplements like magnesium, chamomile tea, vitamin D and lavender essential oils to help minimise stress; and set a consistent schedule that allows you to go to bed around the same time each night.