We all know how great a good night's rest feels. You wake up feeling refreshed, energized and ready to tackle your day. Unfortunately, this rested feeling is the exception and not the norm for many who live busy lives in the modern world, and it's hurting more than our energy levels—it's also harming our hearts. According to the Centers for Disease Control and Prevention (CDC), more than one-quarter of the U.S. population report occasionally not getting enough sleep, while nearly 10% experience chronic insomnia.|
Although it may feel like it, sleep isn't a passive activity, or a luxury for that matter. It's a must for your overall health and well-being and according numerous studies, it's essential for a healthy heart. According to the CDC and numerous studies, not getting enough sleep is associated with a number of chronic diseases, such as diabetes, cardiovascular disease, obesity and depression. Together, these four health conditions prove a powerful case that sleep isn't just beneficial, it's vital.
You may think that Type 2 diabetes is just about keeping your weight down and eating healthy foods, but research has found that sleep also plays an important role. According to a September 2010 study published in the Annals of Epidemiology journal, people who slept less than six hours a night were three times more likely to develop incident-impaired fasting glycaemia (IFG), a condition where your body isn't able to regulate glucose as efficiently as it should. How does this related to heart health? People with IFG have a greater risk of developing Type 2 diabetes and are at an increased risk of heart disease and stroke.
Stress is another important factor when it comes to having a healthy heart. Other studies have shown that a lack of sleep can decrease glucose tolerance and increase the body's production of cortisol, a hormone produced in response to stress (plus we all know how hard it is to make healthy choices and lose weight when you're stressed!). Additionally, researchers have found that lack of sleep results in a 28% increase in average levels of ghrelin, known as the hunger hormone, leading to increased cravings and consumption of foods, making it even harder to prevent or control type 2 diabetes and therefore heart disease and stroke.
There are numerous studies linking insufficient sleep with a number of cardiovascular diseases, including high blood pressure, stroke, coronary heart disease and irregular heartbeat (cardiac arrhythmias).
The most recent shows the negative effects of burning the candle at both ends. Published in the February 2011 European Heart Journal, researchers found that sleeping less than six hours a night due to disturbed sleep gives you a 48 percent greater chance of developing or dying from heart disease and a 15 percent greater chance of experiencing or dying from a stroke.
An earlier study from December 2008 in the Journal of the American Medical Association found that. Compared with people who sleep seven to nine hours a night, people who don’t get enough shuteye are more likely to develop calcium deposits in their coronary arteries, raising their risk for heart disease. In fact, even after accounting for various other causes, researchers found that when sleep-deprived subjects get just one more hour of sleep per night, they had a 33 percent decrease in their odds of developing calcium deposits in their arteries. Although they're not certain why sleep helps keep arteries healthy, researchers hypothesize it helps combat stress, and the fact that when you sleep your blood pressure naturally lowers.
The disrupting sleep condition sleep apnea has a particularly strong connection with heart disease, but it's a bit of a chicken-or-the-egg scenario. A January 2007 issue of the Harvard Heart Letter reported that poor sleep can contribute to heart disease, and heart disease can in turn disturb sleep. Poor sleep increases levels of C-reactive protein and other substances that signal active inflammation in the body. It also revs up the body’s sympathetic nervous system, which can strain the heart. On the slip side, sometimes heart disease is a cause of poor sleep, as many people with heart failure may wake up from due to breathing difficulties.
Being overweight or obese puts strains on the body, especially the heart. According to the CDC, research has found an association between short sleep duration and excess body weight in all demographics, including children. It is believed that sleep in childhood and adolescence is particularly important for brain development and that insufficient sleep in young people may adversely affect the hypothalamus in the brain, which regulates appetite. As mentioned earlier, ghrelin and cortisol are also negatively affected when you don't get enough ZZZs. This can cause an increase in appetite, which can lead to overeating and overweight—a major risk factor for heart disease.
Although the relationship between sleep and depression is complex and not fully understood, sleep disturbance and depression have long been recognized as related factors. According to the CDC, recent research has shown that depressive symptoms may decrease once sleep apnea has been effectively treated and sufficient sleep restored. This close relationship—and depression's negative effects on the heart—makes sleep an important factor in heart health.
Sleeping Better for a Healthier Ticker
So now that you know how important sleep is to heart health, what can you do about it? Follow these tips to get the most from your ZZZs!
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