Matthew McConaughey's long-awaited memoir, Greenlights, comes out on October 20. To whet reader appetites, McConaughey has been dropping a few teasers—such as the revelation that his father, James Donald McConaughey, died after having a heart attack during sex.
James died in 1992, and McConaughey told PEOPLE that his “knees buckled” when his mother told him what had happened. “I couldn't believe it,” he said. “He was my dad. Nobody or nothing could kill him. Except mom.”
It turned out that James predicted how he was going to die. “He'd always told me and my brothers, ‘Boys, when I go, I'm gonna be makin' love to your mother,’” McConaughey said. “And that's what happened. He had a heart attack when he climaxed.”
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Why would someone die during sex?
In short, sex increases a person's heart rate. “Any physical activity will elevate your heart rate—whether you are swimming, running, or having sex, and your risk for a heart attack increases whenever your heart rate is elevated,” Aventura, Florida-based cardiologist Leonard Pianko, MD, tells Health.
What's the connection between increased heart rate and a heart attack? During sex, adrenaline levels increase and heart rate and blood pressure go up, Victoria Shin, MD, cardiologist with Torrance Memorial Medical Center in Torrance, California, tells Health. “This is what we do when we subject patients to ‘stress tests’ in the office or hospital to unmask any underlying heart problems,” she explains. “Sexual activity is a form of ‘stress testing,’ and if someone has underlying heart disease that is undiagnosed, it can manifest as symptoms of chest pain or in the worst case scenario, cause a heart attack or sudden cardiac death.”
Sometimes the terms “heart attack” and “sudden cardiac arrest” are used interchangeably, but it’s important to know they’re not actually the same thing. According to the American Heart Association, a heart attack occurs when the blood flow that brings oxygen to the heart muscle is severely reduced or cut off completely by a blocked artery. If the artery is not reopened quickly, the part of the heart normally sustained by that artery starts to die.
On the other hand, sudden cardiac arrest is caused by an electrical malfunction in the heart that leads to an irregular heartbeat (known as arrhythmia). The heart is unable to pump blood to the brain, lungs, and other organs, and the person loses consciousness within seconds.
While rapid treatment is crucial in both scenarios, sudden cardiac arrest is more likely to happen without warning, while heart attack symptoms can show up hours, days, or even weeks before the heart attack itself.
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How common is it for someone to have a heart attack during sex?
It’s not common. It happens, of course; McCounaghey’s dad is a case in point. But according to a 2017 study published in the Journal of the American College of Cardiology, it’s extremely rare to die from a heart attack during or immediately following sex, even if you have a prior history of heart disease.
The study researchers looked at the community-based Oregon Sudden Unexpected Death Study (Oregon SUDS) database from 2002 to 2015 to determine the frequency of sudden cardiac arrest occurring during or within one hour after sexual activity for all persons over the age of 18. A total of 4,557 cases of sudden cardiac arrest were identified in Portland during the 13-year study period, of which 0.7 percent of them were linked to sexual activity.
“If you have a blockage to your heart and you overexert yourself both physically and emotionally, it may in rare instances precipitate a heart attack,” Dr. Pianko says.
A person's overall health can influence the odds. “For a healthy 50-year-old man, the risk of having a heart attack in any given hour is about one in a million,” Dr, Shin says. “Sexual activity doubles the risk, but it's still just two in a million.”
For men with heart disease, the risk is 10 times higher. “But even for them, the chance of suffering a heart attack during sex is just 20 in a million,” Dr. Shin notes.
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Do only men who have heart attacks during sex?
No, but it’s even rarer for it to happen to a woman, largely because men are more prone to heart disease than women, Dr. Pianko says. Using the 2017 study statistics, one in 100 sudden cardiac arrests in men were influenced by sexual activity. By comparison, the number was one in 1000 in women.
So women don’t need to worry about having a heart attack during sex?
Correct—unless your doctor tells you sex is off the table. “Those who have risk factors for heart disease that are not controlled, such as high blood pressure, diabetes, smoking, obesity, or high cholesterol, should check with the physicians to make sure these factors are controlled,” Dr. Shin says. And if you have any symptoms relating to chest pain, you should definitely get those checked out.
If you or your partner takes erectile dysfunction medications, such as Viagra, you should also check with your doctor to make sure you’re not on any conflicting medications that could cause heart issues, Dr. Shin adds.
Dr. Pianko points out that the long-term benefits of physical activity (including sex) far outweigh the risks. These include stronger bones and muscles, improved mental health and mood, weight management, and a lower risk of heart disease, high blood pressure, high cholesterol, and type 2 diabetes.
Of course, keeping your heart in peak condition is a wise move for everybody. “Sexual activity requires a healthy heart and generally taking good care of yourself,” Robert A. Zaloom, MD, cardiologist and director of the cardiac catheterization laboratory at NYU Langone Hospital–Brooklyn, tells Health. “This means good diet and nutrition and regular exercise, particularly when you’re over 50.”
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