How Could Someone As Fit As Bob Harper Have A Heart Attack?

Bob Harper, the 51-year-old, super-fit host of weight loss reality show The Biggest Loser, had a heart attack while working out in New York City a couple weeks ago, he told TMZ today. A doctor who was also working out at the time kept Harper alive with CPR and defibrillation paddles; Harper was unconscious for two days. He's still recovering in New York, waiting for his doctors to clear him to fly home to Los Angeles.

Harper blamed genetics for the heart attack—his mom died of one at the age of 70. Is that really what's going on here?

First, heart disease is extremely common. It's the leading cause of death in the United States, claiming more than 600,000 lives in 2014. Men in the US have a 1 in 2 chance of developing heart disease, says Martha Gulati, chief of cardiology at the University of Arizona. Still, Gulati realizes Harper's case might seem unique because he is pretty young (under 55 counts as young for a heart attack), and, given his job, is clearly fit as hell.

Family history is one of the first things most doctors would ask about, Gulati says. About 1 in 250 people has one of two forms of Familial Hypercholesterolemia, a genetic condition that can cause heart disease in people as young as 20 if it's not diagnosed. A simple genetic test can identify people with a genetic predisposition towards heart disease so that they can begin making lifestyle changes, such as eating better and exercising more, and start taking meds. But that might not even be necessary if doctors can trace heart disease back over the course of several generations, Gulati says. "The earlier we know the disease is present, the more actions we can take in trying to prevent heart disease [without medication]," she says.

So there's a chance that Harper does actually have a mutation, or some other heritable factor of heart disease. But it's also likely that there are environmental factors that are going on, says Kim Allan Williams, the chief of the cardiology division at the Rush University School of Medicine and the former president of the American College of Cardiology. "You can't exercise your way out of the standard American diet," Williams says. American diets tend to be high in animal proteins, things like eggs, meat, and fish. And while that can help younger athletes beef up more quickly, there's reason to believe that diets that are too high in protein lead to the formation of arterial plaque, which can put them at a much higher risk from heart disease as they get older. (It's possible Harper fell victim to this; in 2015, he told Rachel Ray that he eats two to three eggs for breakfast each morning because he "wants the protein and the fat.")

The American Heart Association has a list of "life's simple seven"—seven things you should do to reduce the risk of heart disease. They are: keep low blood pressure, control cholesterol, maintain a healthy body weight, keep low blood sugar, be active, eat a heart-healthy diet, lose weight, and don't smoke.

What portion of the population does all seven? Just three percent, Williams says. "That leaves everyone vulnerable, and that's why heart disease has been a leading killer of Americans since 1918"—after the Spanish Flu subsided. Obviously Harper has the exercise part all figured out. "But recognition that everyone needs to be on a diet that won't contribute to plaque is something that most people can't wrap their heads around," Williams says.

Just looking healthy isn't good enough, either—you can be skinny and still have high cholesterol and/or high blood pressure, which puts you at an elevated risk of having a heart attack. "The presumption is, because you're healthy, you can't get hypertension, and it doesn't necessarily work that way," Gulati says. Sometimes even doctors fall subject to that bias. "Hypertension is so prevalent in our population it's known as a 'silent killer,' so many people have it and don't know it."

In fact, athletes are some of the hardest patients to care for as a cardiologist, Gulati says, because a lot of them have read misinformation about what's in a healthy diet. Also, there are studies that show that extreme athletes (a qualification that may or may not apply to Harper) have an increased incidence of heart disease. No one is quite sure why.

There are things people can do to put themselves back on track to healthy hearts, even after a heart attack. They can go on completely plant-based diets, like vegetarian or vegan diets, or even the more extreme Esselstyn and Ornish diets, which restrict the number of vegetable fats a person can consume. They can also start taking statins, which lower levels of cholesterol in the blood. These things can reduce the plaque in the arteries and help the blood flow easier in the heart.

If it sounds hard to prevent heart disease as an American, that's because it is—Williams says that even his cardiologist colleagues die of heart disease. Knowing the right things to do for your heart doesn't always mean you actually do them. "For any patient of mine, I ask about any risk factors so we can figure out what are the changes you can individually do," Gulati says. "That's where medicine is an art and a science—it's a balance for each individual." It's probably safe to assume that Harper is finding a new balance of his own as he recovers.

Update: 2/27/17: A previous version of this story identified Martha Gulati as the head of cardiology at Banner University Medical Center Phoenix. Her title has since been corrected.

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