6 Negative effects of sleep loss, and 6 Tips to better more restful sleep
Holistic Health
Reducing your sleep in the name of increasing productivity has long been promoted as essential for success, with many well know business leaders, political figures and entrepreneurs living the reduced sleep mantra. Surviving on 4 hours of sleep is seen as heroic while getting a solid 8 or 9 hours is often seen as lazy. But we are now understanding better the crucial role sleep plays in physical and mental performance as well as long term health and longevity, and you are probably falling short of this ideal amount of sleep. As scientific weight increases on the damaging effects of inadequate sleep The World Health Organisation (WHO in 2007 classed night time work as a probable carcinogen due to its associative increase risk of cardiovascular disease and cancer. Correcting, addressing and improving your sleep maybe one of the single most powerful lifestyle factors in health and fitness, perhaps even greater than diet and exercise, so lets address some of the negative impacts and provide some tools for improving and optimising sleep.
Sleep myth: ”I have survive on 6 hours sleep!”
Many people take pride in the fact they can ”survive” on 6 or even 4 hours of sleep a night. The truth is more recent research suggests 7 to 9 hours is optimal and unfortunately there isn’t much room for negotiation. There is however a subset of the population which seem to be genetically resistant to the negative impacts of reduced sleep…and if you think you won this genetic lottery its worth mentioning that the chances of being whats known as a “short sleeper” when rounded to the nearest whole number and expressed as a percentage of the population is…0%. You are far more likely to get struct by lightning than be a short sleeper.
Hunger & Appetite Hunger is regulated by two hormones; Leptin and Ghrelin. Leptin is known as the satiety hormone and is up-regulated when you are full causing a decrease in hunger. Ghrelin is the ‘hunger hormone’ and acts in opposition stimulating hunger. Sleep deprivation causes an increase in Ghrelin and decrease in Leptin. Multiple studies have shown that the kinds of food we are driven to eat changes when we are not well rested to that of refined carbohydrates, fat rich processed foods even when healthier alternatives are available. Not only do we consume unhealthy food we also consume more calories compared to if well rested. 5 to 6 hours of sleep has been shown to increase caloric intake by 200 to 300 calories daily.
Blood Sugar
Insulin sensitivity is a key factor in long term health and predicts many chronic diseases like obesity and type II diabetes. Sleep loss even for a single night can transform insulin sensitivity to that of a pre- diabetic. Furthermore, sleep loss will change how much and what you eat.
Hunger and Appetite
Hunger and appetite are regulated by two hormones; Leptin and Ghrelin. Leptin is known as the satiety hormone and is up-regulated when you are full causing a decrease in hunger. Ghrelin is the ‘hunger hormone’ and acts in opposition stimulating hunger. Sleep deprivation causes an increase in Ghrelin and decrease in Leptin. Multiple studies have shown that the kinds of food we are driven to eat changes when we are not well rested to that of refined carbohydrates, fat rich processed foods even when healthier alternatives are available. Not only do we consume unhealthy food we also consume more calories compared to if well rested. 5 to 6 hours of sleep has been shown to increase caloric intake by 200 to 300 calories daily.
Reaction Time
Sleep Driving. Everyone is well aware drink driving is dangerous due to decreases in reaction time and judgement, but going 20 hours without sleep will induce cognitive impairment equal to being legally drunk. Worse still reaction time will be slowed when drunk, but phenomena known as micro sleeps can take place at the wheel when driving tired. Your brain will switch to sleep mode for a split second this can even happen with open eyes – rather than a delayed reaction to brake if drunk, no reaction will occur at all..
Sex Drive
Men who sleep 4-5 hours a night regularly will have testosterone levels of a man 10 years older. Testosterone levels in men are a key metric for ageing so regular sleep loss will effectively age you by 10 years. Low testosterone will also impact sex drive, energy levels and muscle mass negatively.
Immune System
Natural killer cells are a type of lymphocyte or white blood cell and play a major role in the destruction of early and pre-cancer cells. A single night of 4 hours sleep will see a reduction of up to 70% in these tumour fighting cells.
Learning & Cognitive Ability
Sleep after learning new tasks is crucial to cementing new information and establishing new neuro pathways. Research with MRI in both animal and human models has shown brain activity increasing in key areas and effectively high speed play back especially with spatial navigation or motor skill learning. So the sleep after learning maybe the most important part of learning and then retention.
Dr Mathew Walker is a professor of neuroscience at University of California Berkly and an expert in sleep research. For a in-depth look into the research carried out at John Hopkins, Why We Sleep by Dr Walker is great read.
6 steps to better, more restful sleep…
1 Regularity. Above all this step is the most powerful in getting regular and restful sleep. Although difficult in a busy life with work, family and commitments to juggle. If possible, pick a sleep and wake time you can do your best to stick to even on weekends, and aim for 7-9 hours a night.
2 Light. Probably the most significant factor in relation to our modern sleep times being pushed later and later is due to artificial light. This has been magnified with mobile devices and screen time. Phones, laptops and tablets emit ‘blue light’ at a wavelength similar to daylight and thus effect circadian rhythm. Spending an hour in front of a screen before bed will delay the onset of melatonin the sleep hormone and reduced it’s peak levels by up to 50%. Avoid screens 2 hours before bed and install an app such as Flux on your devices which warms the light your screen emits. Try turning light around your home off as the sun goes down and of course make your bedroom as dark as possible. Light can also be leveraged to stimulate waking – try to be outside in direct sunlight upon waking.
3 Temperature. Along with light, temperature seem to be key drivers of circadian rhythm. Your body core temperature need to drop between 2-3 degrees Fahrenheit to initiate sleep, and around 60-67degrees Fahrenheit or 15- 19 degrees Celsius optimal for your bedroom temperature. You can also hack this cooling mechanism by taking cold showers, baths or even ice baths if you are brave enough. Although counter intuitive a hot bath will also drop your core temperature. Through vasodilation blood rushes to the skin making it red, once you leave the hot water your body start to dump heat very rapidly the result is a dive in core body temperature.
4 Food. Both being too full and too hungry will impact sleep negatively, the best advice seems to be eat no closer than 2 hours before bed time.
5 Caffeine. We all know coffee and other sources of caffeine ‘wake us up’ try not to consume caffeine past 3pm including caffeinated sodas and tea.
6 Alcohol. Skip the night cap. We know now that alcohol impacts sleep negatively. Having alcohol in your system while sleeping will down regulate REM sleep. Alcohol has been touted as a sleep aid for many years but it important to high light that alcohol is in fact a sedative and sedation is not equal to natural sleep.
If all fails… and you find yourself tossing and turning in bed, the best advice seems to be, give yourself 20 minutes, then get out of bed and engage in an activity like reading in a dim light until you feel the urge to sleep. Staying in bed ‘trying’ to get to sleep longer than 20 minutes will increase your time to sleep and unfortunately counting sheep wont help.