Sleep is essential for a healthy heart. People who don't sleep enough are at higher risk for cardiovascular disease—regardless of age, weight, smoking and exercise habits. One study that examined data from 3,000 adults over the age of 45 found that those who slept fewer than six hours per night were about twice as likely to have a stroke or heart attack as people who slept six to eight hours per night.
It's not completely clear why less sleep is detrimental to heart health, but researchers understand that sleeping too little causes disruptions in underlying health conditions and biological processes like glucose metabolism, blood pressure, and inflammation.
One of the reasons we know how vital sleep is to the heart is that patients with sleep apnea (which causes them to wake frequently throughout the night) often have compromised heart health. This is because without long, deep periods of rest, certain chemicals are activated that keep the body from achieving extended periods in which heart rate and blood pressure are lowered. Over time, this can lead to higher blood pressure during the day and a greater chance of cardiovascular problems. Many studies have shown the relationship between sleep apnea and cardiovascular disease. One found that over an eight-year period, men with severe sleep apnea were 58 percent more likely to develop congestive heart failure than men without the nighttime breathing disorder. But it doesn't take a severe underlying sleep disorder to see effects on the heart. Poor sleeping (as a result of changing work schedules or poor sleep habits, for example) can put you at risk as well.
Recent research has shown that too little sleep earlier in life could take its toll as well. For example, in one study, adolescents who didn't sleep well were at greater risk for developing cardiovascular problems. Those teens had higher cholesterol levels, a higher body mass index, larger waist sizes, higher blood pressure, and an increased risk of hypertension. It's easy to see how these alterations in childhood health could snowball into major concerns later on, and why it's important to protect sleep at every age