Feeling like a wreck? You’re not alone. We are increasingly becoming a sleep deprived society, and you’re about to find out why this is such a disaster, and why you see so many of “the walking dead” wandering around your workplace. According to Andrew Calvin, Assistant Professor of Medicine at the Mayo Clinic, “Sleep deprivation is a growing problem, with 28 percent of adults now reporting that they get six or fewer hours of sleep per night.” (1) Researchers in one study demonstrated that by depriving a group of people of one hour and 20 minutes of sleep each day (compared with a control group) caused them to consume an average 549 additional calories each day! (1) That has to add up, over time.
Sleep is innately connected to numerous hormonal and metabolic pathways in the body, and is essential for maintaining good health and wellbeing throughout life (2). Getting enough quality sleep is essential for maintaining mental and physical health (not to mention, not becoming a zombie). In fact, numerous studies, like the one above, have shown that the wrong amount of sleep (whether deprivation or excessive slumbering) can have significant consequences on health outcomes including weight, cardiovascular disease, diabetes, high blood pressure, general health and mortality and adults and children (2). It may seem obvious why remaining in bed all day is bad for you, but how could losing sleep be problematic? Read on!
Sleep & Weight Gain
In a study of 1024 participants in the population-based Wisconsin Sleep Cohort Study, researchers found that BMI increased in proportion to decreased sleep (3). In other words, less sleep = more weight. In fact, population studies across numerous age groups show a dose-response relationship between short sleep duration and high body mass index (BMI)— the shorter the sleep, the greater the obesity (3).
One such reason may be that sleep restriction can affect internal processes related to energy balance, such as impairing glucose (sugar) metabolism and increasing appetite. Sleep restriction can also affect external factors such as food choices, increased time available to consume food, reduced physical activity and energy expenditure (2).
Sleep & Messed Up Hormones
Sleep deprivation has been linked to alterations in important appetite-regulating hormones, which is troubling when we live in a society where you don’t have to chase down and club your food before eating it. Hormones making you feel hungry? The fridge is never far away.
Leptin and ghrelin are two hormones which have been implicated in poor sleep (4). Leptin is the “stop eating now and start burning” hormone, released from fat cells. When it is released, leptin helps lower appetite and suppress food intake whilst also stimulating energy expenditure (4). Ghrelin is the “must eat now” hormone, primarily released from the stomach. When released, it stimulates appetite, fat production and body growth, all of which increase food consumption and body weight (8).
Research has shown short-duration sleep (~5hrs) is associated with low levels of leptin (not enough “stop eating” hormone) and higher levels of ghrelin (too much “eat now and store it up” hormone), compared to longer-duration sleep (~8hrs). It is believed that these differences in leptin and ghrelin are likely responsible for an increase in appetite, and could account for higher BMI ranges observed with short sleep duration (4).
Sleep & Chronic Diseases
Want to die early? No problem. Just starve yourself of sleep.
Numerous studies have suggested that sleep loss (less than 7 hours per night) may have wide ranging effects on the cardiovascular (heart and blood vessels), endocrine (hormone), immune (disease fighting) and nervous systems, including obesity in both adults and children, prediabetes and type two diabetes, heart disease and high blood pressure, alcohol use, anxiety and depression (5). In other words, starving yourself of sleep can mess up your heart, blood vessels, hormones, immune system, brain and nerves.
Evidence that sleep is linked with chronic disease is abundant. Two large studies found an association between sleep loss and prediabetes and type two diabetes (5). In the Sleep Heart Health Study, adults who reported five hours of sleep or less were 2.5 times more likely to have diabetes compared to those who reported 7 to 8 hours per night (5). Several large population studies suggest sleep loss and sleep disorders are also associated with heart attacks and perhaps even stroke. There are numerous potential reasons why including increases in blood pressure or prediabetes which both have negative consequences on heart health (6).
Sleep & Mental Health
It is probably empirically obvious to most of us that no sleep is “not thinking straight”. Mental health, mood and behaviour may also be casualties of sleep deprivation. Adults with chronic poor sleep have a higher incidence of mental distress, depression, anxiety, alcohol use and behavioural issues. However, the jury is still out on whether this is cause or effect or (more likely) a two way relationship. Is it sleep that influences mood and anxiety, or vice versa (6)? Either way, we all know we don’t feel great after being deprived of sleep for a few weeks… Just ask any parent of a newborn!
Tips For A Good Night’s Sleep
So to sum this litany of sleep-deprived woes up, we want to offer this list of our top tips for getting a good night’s sleep:
- Invest in a supportive and comfortable mattress and pillow.
- Try and stick to a sleep schedule. Keeping to a regular bedtime and waking time will help regulate your body clock.
- Develop a relaxing night time ritual such as a having a warm shower and cup of herbal tea. Avoid activities that cause you excitement or stress, such as opening up your work emails right before bed.
- Move your body daily. Exercise can help you get a good night sleep, but avoid it immediately before bed.
- Avoid bright lights such as your phone or computer for at least 30mins before bed. That includes watching TV in bed.
- Limit your caffeine, alcohol and sugar intake before bed, and avoid food for one to two hours before sleep.
- Knutson KL. Impact of sleep and sleep loss on glucose homeostasis and appetite regulation. 2007. Sleep Medicine Clinic. 2(3): 187-197
- Taheri S, Lin L , Austin D, Young T, Mignot E. Short sleep duration is associated with reduced leptin, elevated ghrelin, and increased body mass index—A population-based study. 2004. PLoS Medicine. 1(4): 62.
- Prinz P. Sleep, Appetite, and Obesity- What Is the Link. 2004. PLoS Medicine. 1(4): 61; 1(4): e61.
- Gottlieb DJ, Punjabi NM, Newman AB, Resnick HE, Redline S, Baldwin CM, Nieto FJ. Association of sleep time with diabetes mellitus and impaired glucose tolerance. Archives of Internal Medicine. 2005;165(1):863–867.
- Hasler G, Buysse DJ, Gamma A, Ajdacic V, Eich D, Rossler W, Angst J. Excessive daytime sleepiness in young adults: A 20-year prospective community study. Journal of Clinical Psychiatry. 2005;66(5):521–529.
- National Sleep Foundation. Healthy Sleep Tips. 2017. Available from; https://sleepfoundation.org/sleep-tools-tips/healthy-sleep-tips
- Korbonits M, Goldstone AP, Gueorguiev M, Grossman AB. Ghrelin—A hormone with multiple functions. Front Neuroendocrinol. 2004;25:27–68.