Sleep apnea is a condition that causes a person to repeatedly stop breathing while he or she is asleep. This lowers a person’s blood oxygen level, and results in the same physiological response as when a person is under great stress. The heart beats faster, blood pressure goes up, and the body releases stress hormones that are detrimental to your health.

Over time, these changes in the body can cause serious health problems such as high blood pressure, heart disease, and metabolic syndrome. In fact, it’s thought that 70 percent to 80 percent of people with sleep apnea also have metabolic syndrome, a cluster of conditions including excess belly fat, high blood pressure, and others that when occurring together increase heart disease risk.

Sleep apnea occurs most commonly in men, especially those 65 and older, as well as those who are overweight or smoke. Sleep apnea is considered a “silent killer” because those who have it are not aware of it. But if you are a loud snorer or you experience daytime sleepiness, these are clues you can’t afford to ignore.

The good news is that with treatment, sleep apnea can disappear. The main way to treat sleep apnea is by sleeping with a CPAP (continuous positive airway pressure) mask, which provides continuous air pressure through the night that keeps the breathing airwaves open.

In a recent study published in The New England Journal of Medicine, researchers outfitted 99 patients with a CPAP device for three months and then gave them a fake one to use. They found that metabolic syndrome disappeared in those who used the real device, but returned when the fake CPAP mask was used.

So if you find yourself yawning during the day, or your spouse complains that you snore and sometimes stop breathing, get checked for sleep apnea. It could save your life.