Following the release of the Sleep Health foundations survey, and our sleep infographic, we look at the current studies around sleep in greater depth, and gives you some tips for a good night’s snooze.
With the help of the Sleep Health Foundation, and especially sleep psychologist Dorothy Bruck, comparethemarket.com.au pulled together some research based around their annual sleep survey. The results revealed some interesting sleep patterns and behavior, including patterns that seem to emerge with age and the rise of technologies; you can view the full report here.
Our sleep patterns and aging
The sleep survey revealed we go to sleep at 23:14 on average, and wake at 06:32, achieving 7 hours and 18 minutes of sleep. This is consistent with the guidelines to get 7-9 hours of sleep, even if it is towards the shorter end of the spectrum. As these figures are broken down into age category, there are obvious trends in the data.
What is clear is that the amount of sleep respondent’s reported decreased with age. 18-34 year olds slept an average of 7 hours and 37 minutes, the 35-45 age group slept 7 hours and 19 minutes, and the 55+ group slept for 6 hours and 50 minutes. This is perhaps surprising as we may think that older people sleep longer. However, delving further into the data reveals that the percentage of people who napped during the day also increased dramatically with age. Only 11% of 18-34 and 35-54 year olds took a nap during the day preceding the survey, whereas double the amount of people aged 55+ napped the previous day.
Another interesting finding includes the wake and sleep times of each age group. All age groups went to sleep between 23:03 and 23:30, but respondents woke earlier with each age group. Dorothy Bruck said, “The findings agree with the body clock changes that we know happen across the adult life-span. Young adults tend to want to stay up later and older adults feel ready for sleep a bit earlier. This shift in the preferred timing of the body clock has even been documented in adolescent monkeys – so it’s not just related to lifestyle.”
As we age, the study shows that we awaken more during the night, and generally achieve a lower quality of sleep. So what could be affecting the sleep of the older generation?
- Napping – As described above, the number of people napping increased with age
- Caffeine – According to the study, caffeine consumption increased dramatically with age. From an average of 99mg for the youngest age group, to 177mg in the oldest. The older generation is consuming almost double the amount of caffeine, which could be having an effect on their ability to get a good night’s sleep.
- Alcohol – The number of respondents who drank alcohol in the 24 hours prior to the study also increased dramatically with age, from 19% in the youngest group, to 31% for 35-54 year olds, and 51% for the oldest study group.
- Sleeping Medication – The amount of sleep medication consumed increased with age too, with 3% of 18-34 year olds, 7% of 35-54 year olds, and 15% of the 55+ age group reporting taking sleeping medications in the previous day.
Dorothy Bruck says of the data, “It was surprising to see that older people are not doing themselves any favours drinking lots of alcohol and coffee; mood-altering substances which have been proven to be detrimental to a good night’s sleep. As they age, people should really be consuming less of these, not more.”
Disturbances in the night
Dorothy Bruck says being disturbed during the night is quite normal; “Normal sleep does not mean unbroken sleep. It is quite normal to have several brief awakenings during the night and absolutely normal to have thoughts going round in the brain during sleep.
66% of people surveyed said they were disturbed during the previous nights sleep, here’s a top 10 list of what was keeping people from their 40 winks:
- Toilet: 36%
- Thoughts on mind: 21%
- Aches/pains: 16%
- Noise: 14%
- Partner: 13%
- Temperature: 8%
- Children: 6%
- Work: 4%
- Pets: 4%
- Dreams: 2%
So, what is the trick to getting the best quality sleep possible? Dorothy Bruck says that although waking in the night is normal, getting back to sleep can be the difference between a good night sleep, and being blurry eyed in the morning. She says, “When awake, the secret is to make the thoughts neutral and boring – not plotting revenge on your boss or planning your next dinner party.” Controlling thoughts can be tricky especially if you’re anxious, but what you do to prepare for sleep can help.
Our sleep behavior and technology
In another study from the Sleep Health Foundation, 45% of adults used a laptop, electronic device, or watched TV in bed. In addition, 30% have a phone by the bed that is not in silent mode, so can be awoken by buzzing’s and beeps at any time of night. Dorothy Bruck says, “We now know that the blue light from electronic screens suppresses a sleep-promoting hormone called melatonin”. Dorothy suggests a 1-2 hour buffer zone before bed, where electronics are banned so the body can realise it’s time to sleep.
Four further studies on sleep and the body may help to shed a little light on some of the ramifications of poor sleep, in terms of our health.
Sleep and self-esteem
One study published in the International Society of Behavioral Medicine suggested a link between positive personality traits and sleep quality. The 1,805 study participants, all aged between 30 and 84, were asked to self-assess their self-esteem. The results showed that those who suffered from insomnia symptoms scored lower for positive personality traits, with little influence from the age and sex of the person. Those who slept less than 6 hours were less optimistic than those who slept 7-8 hours, however, those who slept longer than 9 hours also showed low self-esteem.
These figures may seem surprising, as we might not readily associate our sleep patterns with our self-esteem. However, perhaps they make more sense when thinking about how we feel when we haven’t had a good night’s sleep – tired, irritable and even moody. When the body isn’t recharging properly we can struggle to function well, so it perhaps isn’t too much of a stretch to think that this will have an effect on perceptions of ourselves.
Sleep and the brain
An interesting study published in the September edition of American Society of Plant Biologists by a molecular biologist called Albrecht von Arnim suggests a link between sleep and activity in brain cells. His study was conducted on plants, but Arnim says it could translate to humans.
In the study, Arnim looked at protein synthesis, the process by which cells generate new proteins. The renewal of proteins means the plant can generate new cells and grow, quite important in the life of all organisms. Arnim found that protein synthesis in plants changed depending on the time of day, and the organism’s internal clock, or circadian clock. From this, Arnim put forward that if we disrupt our sleep patterns, we may do more than awake in a bad mood – we could actually be disrupting the production of new cells in our bodies. These cells in humans are responsible for muscle action, brain activity and growth, so if Arnim’s study of plants could translate to humans, sleep could prove to be vital to physical development.
Sleep and weight
There are a number of studies that link poor sleep with weight gain, both in children and adults. One of the largest adult studies that made this link was conducted by the Nurses Health Study over 16 years, following 68 thousand middle-age women. The study found that women who slept 5 hours or less each night were 15% more likely to be obese. Another study from the same organisation found a link between women who did shift work and obesity, finding that the longer women worked a rotating night shift, the more likely they were to be overweight.
Interestingly, other studies, such as; “Short sleep duration as a possible cause of obesity: critical analysis of the epidemiological evidence” published in Obesity Reviews in 2011 claim there is a link between obesity and sleep in young adults, but not so with older adults.
Researchers speculate that there are a number of ways that sleep could influence body weight:
- Increasing hunger: Hormones influencing appetite can be altered by sleep patterns – see the study here.
- More waking time to eat: One study published in the American Journal of Clinical Nutrition 2009 found a link between waking hours and the amount of snacks eaten, and therefore obesity.
- Poor sleep equates to poor food choices – this is not backed by observational studies, but one paper from Japan found that workers who slept for less than 6 hours ate out more and had irregular meal times.
- Less sleep equals less exercise – If people are tied they may move less. Some studies have shown sleep deprived people spent more time watching TV, and less time being physically active.
- People who sleep less have a lower body temperature, so burn less energy – see the report here.
Sleep and memories
Our final study from eLife suggests that sleep plays a part in forming memories. The study found that even after a short nap, memories associated with reward were retained with more accuracy. The researchers are not sure how, but information associated with low reward wasn’t so easily retained, and high reward information was transferred to areas of the brain that is responsible for long term memory. Additionally, people who slept were also more confident of their answers, even after three months. This could help towards understanding why appropriate sleep is generally associated with positive learning outcomes.
Tips for tip top sleep
As we can see from the studies above, getting regular, quality sleep is likely to have positive effects on our health and wellbeing. With this in mind, here are 11 tips from the Dorothy Bruck and the Sleep Health Foundation on getting a good night’s sleep:
- Have a regular sleep pattern
- Aim for 7-9 hours
- Keep technology out of the bedroom
- Relax for an hour before bed
- Get comfortable
- Avoid caffeine, cigarettes and alcohol
- Avoid napping if possible (adults only!)
- Don’t go to bed hungry, or too full (and try to avoid midnight snacking!)
- Get some sunlight during the day
- Limit fluids an hour before bed
Seek medical attention if you regularly don’t sleep well.
Do you need a sleep assessment?
If you are regularly experiencing poor sleep, it could be a good idea to seek professional help. To find out what’s going wrong at night, you might be required to undergo a sleep study. This often involves visiting a sleep laboratory, and staying overnight whilst you’re monitored. The study measures many things that could indicate why you’re not sleeping well, including you breathing, blood oxygen level and body position. It’s best to contact your GP to discuss you options if you think a sleep study could help, or for more information on what to expect form a sleep study, this fact sheet is useful.
Overall, sleep is our body’s way of taking a rest, and in today’s bustling society with so many commitments, we all need to take a rest and recuperate every night.