Not getting enough sleep isn't just about dark undereye circles or embarrassing yawns during meetings. The consequences of insufficient sleep can have a serious, widespread toll on your health, in ways you may not even realize.
When talking about insufficient sleep, it's important to know just what insufficient means. According to the National Sleep Foundation, here's the breakdown of sleep time recommendations for teens and adults:
- Teenagers (1417 years): 810 hours, but 711 may be appropriate
- Adults (1864 years): 79 hours, but 610 may be appropriate
- Older adults (over 65 years): 78 hours, but 56 hours or up to 9 hours may be appropriate
Nightly hours of sleep below these minimums begin to fall into the dangerous zone of insufficient sleep. The consequences to your health increase the lower that number falls.
While most teens have no problem sleeping well past noon when given the opportunity, many adults start to lose their grip on good sleep as they get older. The U.S. Centers for Disease Control and Prevention (CDC) estimates that 30% of adults sleep less than six hours per night. That's enough to qualify as a public health epidemic.
Sometimes, insufficient sleep is the result of a sleep disorder like insomnia or sleep apnea which we talked about in a recent blog about sleep studies. Other times it's a combination of lifestyle factors, anything from too much caffeine to stress and anxiety to hectic work schedules.
Sleep expert and neurologist Holly Skinner, DO, says quality sleep is being threatened by the broader changes to our lifestyle, especially changes in how we work. These include ever-increasing work hours, the use of lighted electronic devices at night and the blurring of the division between work and home time.
In fact, people in Western countries now sleep a full 90 minutes fewer each night than they did less than a century ago.
No aspect of our health is untouched by sleep deprivation.
In fact, all living organisms are designed to sleep, because of its restorative and healing effects on our bodies and mind, Dr. Skinner says.
Here are just some of the ways chronic sleep deprivation can harm your health:
Heart Attack or Stroke. When our brains are activated during sleep, they can trigger a fight-or-flight response, leading to increases in blood pressure and heart rate. Over time, this can lead to high blood pressure and diabetes, both of which are risk factors for heart disease and stroke.
Alzheimer's Disease. With a good nights sleep, plaques associated with Alzheimer's Disease get cleared from the brain; without it, these plaques can build up and begin to degrade the brain. This can eventually lead to Alzheimer's disease. Moreover, as these plaques accumulate, they limit the brain's ability to sustain sleep, leading to a vicious cycle.
Weight Gain. Insufficient sleep interferes with the hormones of the body that signal fullness and hunger, leading us to pack on pounds.
High Blood Sugar. Short sleep can negatively affect how cells respond to insulin, in turn leading to prediabetic hyperglycemia, or high blood sugar.
Cancer. Not only does reduced sleep make us more susceptible to common colds and viruses, it can leave us vulnerable to certain cancers. Even a single night of four or five hours sleep can cause a drop in the body's cancer-fighting cells.
High Risk of Accidents. Those who drive a car with less than five hours sleep are over four times more likely to be involved in a crash. Workplace injuries also increase with lack of sleep.
Poor Mental Health. Depression, anxiety and mood swings are just a few of the mental side effects of reduced sleep. In adolescents, sleep deprivation is linked to bullying and aggression.
Early Mortality. In general, both short and long sleep durations are associated with higher risks of death from any cause.
When you consider the many ways in which sleep deprivation can harm your health, it's not hard to see how sleep is about more than feeling alert.
Sleep helps us function optimally, maintain our cognitive abilities in the long term and prevent chronic disease that can shorten our lives, Dr. Skinner says.