We spend a third of our lives sleeping so it makes sense that the quality of that sleep would have an impact on health. Good quality sleep results in people feeling generally happier, healthier and more alert.
Poor sleep can have a negative impact on several aspects of health. Many of the major restorative functions in the body (muscle growth, tissue repair, protein synthesis and the release of growth hormones) occur during sleep so it is vital to our bodies’ optimum functioning.
Lack of sleep has both long- and short-term effects on our physical and mental health. In the short term, a lack of sleep can negatively impact judgement, mood, the ability to learn and retain information, concentration, increasing the risk of serious accidents and injury. Studies have shown that symptoms of a loss of sleep mimic those of chronic stress including increased blood pressure, inflammation and impaired control of blood glucose.
In the long term, chronic sleep deprivation may lead to myriad health problems. It’s not all gloom and doom, though, as many health issues exacerbated by lack of good quality sleep also improve if sleep is enhanced. Here are some of the major issues that could be made worse by inadequate or inferior sleep:
Lack of sleep is linked to weight gain and people who sleep for less than six hours a night are more likely to have a higher Body Mass Index. Sleep deprivation is now considered as much as a risk factor for obesity as overeating and lack of exercise.
You can blame it on hormones. During sleep, the body secretes hormones that help to control appetite, energy, metabolism and process glucose. The result of too little sleep is simple: a lack of these hormones leads a detrimental effect on the body’s ability to metabolise.
In addition, too little sleep increases the product of other hormones – cortisol, the stress hormone, and insulin – both of which lead to the storage of fat.
We also need a balance of hormones which regulate appetite, namely leptin and ghrelin. Too little sleep leads to an excess of ghrelin which stimulates appetite and not enough leptin, the hormone that helps your brain recognises when you are full. All of this leads to weight gain and, eventually, obesity.
Closely linked to obesity, diabetes can be triggered by a chronic lack of sleep as it influences the way the body processes glucose and carbohydrates. Less sleep leads the body to process glucose more slowly by affecting the production of insulin. The body's reaction to sleep loss can resemble insulin resistance, a precursor to diabetes. Insulin's job is to help the body use glucose for energy. In insulin resistance, cells fail to use the hormone efficiently, resulting in high blood sugar and eventually diabetes.
HEART DISEASE AND HIGH BLOOD PRESSURE
Even short periods of poor sleep can lead to elevated blood pressure and studies have shown that a single night of inadequate sleep in people who suffer from hypertension can cause elevated blood pressure throughout the following day. Obstructive sleep apnea (OSA), which causes poor sleep, seems to be connected to heart disease. Sufferers of OSA are woken up multiple times a night. In addition to these sleep disturbances, they experience brief surges in blood pressure each time they wake up. Over time this can lead to the chronic elevation of blood pressure (hypertension)which is a major risk factor for cardiovascular disease.
Sleep promotes healing. Think how you recover much more quickly from a cold when you stay in bed than when you push yourself. It therefore makes sense that enough sleep promotes good immune functioning and lack of sleep supresses immune function. This means that you are not only more susceptible to contracting an illness but have less of a chance of successfully fighting it if you don’t get enough sleep.
If you think about how irritable and moody you feel after a single bad night’s sleep, it’s not difficult to understand that long-term insufficient sleep could lead to serious mood-disorders including depression and anxiety. In one study, subjects who slept for four and a half hours per night reported feeling more stressed, sad, angry, and mentally exhausted and in another they showed declining levels of optimism and sociability.
The good news is that all symptoms of poor mental health displayed by participants in sleep studies improved when they returned to good sleeping habits.
Considering how lack of sleep has a detrimental effect on so many areas of health, it’s not surprising that chronic poor sleep is related to lowered life expectancy. Several studies show that less than five hours’ sleep a night leads to as much as a 15% increase in the risk of mortality from all causes. It is essential to discuss sleeping problems with your doctor and endeavour to improve both the quality and quantity of your sleep. If your sleep is being affected by a snoring partner, address the issue sooner rather than later as it could be detrimental to both your health and theirs in the long term.