Can You Be Fat But Fit?

Wouldn’t it be great if we could eat all the ice cream and french fries we wanted and still be healthy? The idea that you can be fat but fit is increasingly bandied about these days, spurred by studies that suggest an extra layer of fat could have a protective effect on our bodies.

So can you carry extra pounds but still be healthy? The latest research suggests the notion is misguided.

In the largest study of its kind, scientists from Imperial College in London and the University of Cambridge found that among people who are internally “fit,” those who are overweight or so heavy they are obese have a higher risk of heart disease. Fit was defined as having normal levels of cholesterol, blood pressure and other metabolic markers of cardiovascular health.

“This observation refutes the concept of healthy obesity,” says Ioanna Tzoulaki, a senior lecturer in epidemiology at Imperial College London and one of the lead authors of the study, published in August in the European Heart Journal. Researchers used data from more than half a million people in 10 European countries to show an increased risk of heart disease for overweight and obese people whose metabolic markers are in the normal range, a risk elevated by 26 and 28 percent respectively.

Researchers point out that studying what they call the “fat but fit myth” is relevant for people who are considered healthy inside. Those who have high blood pressure, high cholesterol or diabetes remain in the highest risk group for heart disease, regardless of their size.

Tzoulaki says that for overweight people, it might be only a matter of time until those symptoms appear. “One possibility could be that they are not yet metabolically unhealthy but they are en route to becoming unhealthy,” she says.

There are many reasons this can happen, including that over time, fat tissue can influence high cholesterol. It also correlates with inflammation markers that are associated with arteries becoming narrowed and stiff, eventually leading to heart disease.

Delayed Consequences

Many illnesses of the heart, like coronary artery disease, take years to develop as plaque builds up, causing arteries to constrict and decreasing blood flow to the heart.

Dangerous plaque material attaches to our heart’s arteries most often when we regularly eat high-fat foods, lead a sedentary lifestyle and smoke, says Dr. Aaron Baggish, director of the cardiovascular performance program at the Massachusetts General Hospital Heart Center. Once the plaque takes up a home in the arteries, it’s generally there forever.

A healthy lifestyle and medication can help stop the progression of coronary artery disease by shrinking and stabilizing the plaque so it’s less likely to rupture and cause a heart attack, and there are medical procedures to open arteries if they have become precariously narrow. But doctors say once coronary artery disease is diagnosed, the best they can do is help manage it.

All Shapes and Sizes

Baggish, who is the team cardiologist for organizations including US Soccer and the New England Patriots, notes that in his practice, he sees patients of all sizes and shapes who have heart disease, some caused in part by unhealthy life choices and some by genetics.

He emphasized that signs such as high blood pressure, high cholesterol, diabetes and other markers of an unhealthy heart are the most powerful indicators of whether someone will develop heart disease. “You’re much better off being overweight and metabolically healthy than having uncontrolled blood pressure,” Baggish says.

Yet weight is an important factor in cardiac health. “For patients who want to optimize their heart health, weight control is one component of that strategy,” he says.

Big Benefits

According to the World Health Organization, more than 1.9 billion adults worldwide are overweight. Of those, more than 600 million are obese. In the United States, more than one-third of adults are obese, bringing complications that have long been correlated with chronic illnesses such as heart disease, stroke, lung disease and cancer.

The terms overweight and obese are based on body mass index, or BMI, which is body weight in relation to height. A normal BMI range is 18.5 to 24.9, overweight BMI is 25 to 29.9 and obese is anything higher. For example, a woman who is 5 feet, 5 inches tall and has a normal BMI would weigh between 111 and 149 pounds. A man who is 6 feet tall and has a normal BMI would weigh between 138 and 184 pounds.

Doctors say most of their patients who are overweight or obese want to lose the extra pounds, but it’s hard to do. Baggish estimates that to lose weight, a person needs to cut calories and also exercise about 300 minutes a week, or double the amount of exercise the American Heart Association recommends to promote cardiovascular health. It can be demoralizing to work hard and not lose weight, but being fit has big benefits, no matter a person’s size. “Even if you don’t lose all the weight you’re shooting to lose, you’re strengthening your heart to help your long-term cardiovascular risk with exercise,” says Dr. Neel Chokshi, medical director for the sports cardiology and fitness program at Penn Medicine and an assistant professor of clinical medicine in the Perelman School of Medicine at the University of Pennsylvania.

Exercise is critical for everyone, but particularly so for people who are overweight or have heart disease, he says. “If you’re overweight, you’re at higher risk for a heart attack, but people who are in better shape tolerate heart attacks better,” Choski says. “The heart attacks are smaller, and people bounce back much better.”

Allison Klein



View all posts by