It is estimated that over 50 million Americans report difficulty sleeping. With our busy American lifestyle, where we are overcommitted in both our work schedules and personal lives, it may seem that sleep is indeed a luxury. But a good night’s sleep is increasingly recognized as an important factor in maintaining good health overall, and good cardiovascular health in particular.
Sleep disturbances and heart health
Disrupted sleep has been implicated in cardiac disease risk in multiple ways. Insomnia and obstructive sleep apnea (OSA) are the most common sleep disturbances and affect sleep duration and sleep quality, which in turn impact cardiometabolic health. OSA is a serious sleep disturbance in which breathing stops or becomes shallower multiple times each night because the tongue or throat tissues block the airway. It is estimated to affect somewhere from 10% to 25% of adults. Insomnia is also a common sleep disturbance, estimated to affect up to 25% of adults, but is frequently undiagnosed. The American Heart Association (AHA) recommends screening for OSA in everyone with heart failure and atrial fibrillation.
Poor sleep leads to poor food choices
In a recent study published in the Journal of the American Heart Association, researchers analyzed the relationship between sleep and eating patterns — which also affect cardiovascular health — in almost 500 women. The women reported on their sleep quality, the amount of time it took to fall asleep, and whether or not they had insomnia. They also reported on their dietary habits.
The study found that those who had the worst sleep quality consumed more added sugars than women with better sleep quality. Women who took longer to fall asleep consumed more calories and more food overall. And women with poor-quality sleep were more likely to overeat and to make unhealthy food choices. Poor diet is known to increase risk of cardiovascular disease (CVD).
Since this study is observational, we cannot draw conclusions of causality. We can surmise that the sensation of being satisfied or full is affected by sleep deprivation, likely via complex hormonal signaling. We can also consider that poor diet (too much of the wrong kinds of food) may affect our ability to fall asleep and stay asleep. In addition, poor diet and overeating are associated with obesity, an important risk factor for CVD.
Consistent sleep duration, regular bedtime are good for the heart
Another recent study, published in the Journal of the American College of Cardiology, linked sleep irregularity to the development of CVD. This study followed nearly 2,000 adult men and women without CVD for five years. Participants wore wrist trackers to track sleep and activity. Study participants also completed a comprehensive sleep study and answered questions about their lives, including diet.
Researchers found that irregular sleep duration increased the risk of heart disease. Those with the most irregular sleep duration and variable bedtimes had more than double the risk of developing heart disease, compared to those with less variability in sleep duration and more consistent bedtimes. Researchers think that multiple factors could link irregular sleep patterns with harmful metabolic changes, such as obesity, diabetes, and elevated cholesterol, all of which impact CVD risk. And since our metabolic health may be affected by sleep, our dietary choices may be even more important when we are sleep deprived.
Prioritize good sleep for better heart health
There is growing evidence that sleep is important to optimal health. These two recent studies raise the important question of how sleep affects our diet and cardiovascular health.
Pay attention to how long and how well you sleep at night. If you have insomnia or poor-quality sleep, talk to your doctor about having a formal sleep study and about factors that could help to improve your sleep.