The researchers found that good quality sleep can make up for sleeping less than the recommended seven to nine hours when it comes to boosting the immune system and fighting viruses.
The study was conducted on individuals who had just joined the military and were assessed over a 12-week period. Researchers found the new recruits slept two hours less a night than they did before they joined the military.
However, despite this, the recruits still described their quality of sleep during their training as good quality. Nevertheless, those who reported sleep restriction during the day were almost three times as likely to suffer from a respiratory infection.
Said results were published after taking into account other risk factors for illnesses, such as the time of year and lifestyle habits, such as smoking.
In a twist to the research, the team found the increased risk of a respiratory infection was only experienced in those who experienced poor quality sleep rather than those who experienced good quality sleep over the shorter period of time.
Professor Neil Walsh said of the research conducted by the University of Liverpool: “There are two very key messages here: firstly that restricted sleep patterns can result in more frequent illness, and secondly and more surprisingly, that sleeping well can trump sleeping long in terms of our immunity to illness.
“That is an extremely useful message in our hectic world where sleep is often sacrificed for other pursuits.”
While the message from this observational study may be clear, that sleep quality matters as well as sleep amount, what is key is helping more people to sleep well; on this Professor Walsh has five tips.
These five tips include:1. Adopting a consistent sleep schedule (similar bed and wake time), including weekends2. Avoiding large meals, caffeine and alcohol close to bedtime3. Ensuring the bed and pillow are comfortable and that the room is cool, dark and quiet4. Establishing a relaxing bedtime routine5. Undertaking exercise during the day to help fall asleep.
Professor Walsh also recommended going screen-free for 30 minutes before bed time and going to bed when feeling sleepy as part of his recommendations for better quality sleep.
Meanwhile, although this study claims to be the first of its kind, this may not be the case as another study published in the Journal of Experimental Medicine this month also looked at the impact of sleep on the immune system.
This time, rather than assess new military recruits, the study looked at 14 adults as part of a clinical research trial and modelled sleep restriction by asking them to deliberately reduce how much they slept.
After six weeks, the team established, in common with the UK study, that sleep can help support the immune system with those adults who slept less having more markers for inflammation.
In their report, they said: “Combining haematopoietic clonal tracking with mathematical modelling, we infer that sleep preserves clonal diversity by limiting neutral drift. In humans, sleep restriction alters the HSPC epigenome and activates haematopoiesis.
“These findings show that sleep slows decay of the haematopoietic system by calibrating the haematopoietic epigenome, constraining inflammatory output, and maintaining clonal diversity.”
What this means is that the lack of sleep disrupts the immune cells in such a way that negatively impacts the immune system.
Director of the National Centre on Sleep Disorders Research Marishka Brown said: “Sleep impacts optimal functioning of nearly every cell and organ in the body.
“The mechanistic insight from this study supports findings from larger population studies, which have shown that sleep can have a protective effect against a variety of conditions, including heart disease, cancer, and dementia.”
Meanwhile, senior study author Filip Swirski added: “What we are learning is that sleep modulates the production of cells that are the protagonists – the main actors – of inflammation. Good, quality sleep reduces that inflammatory burden.”
On the change in the stem cells Swirksi reassured that “the change isn’t permanent, but they continue to self-replicate at a higher rate for weeks” suggesting the change can be reversed by higher quality sleep.