Rethinking Conventional Wisdom on Heart Disease

Our understanding of the link between diet and cardiovascular health has been too simplistic, not always supported by science—and corrupted by big business

cardiovascular health, cardiovascular disease, health and wellness, mayo clinic, heart disease, medical research, university of minnesota

Illustration by Darren Gygi


Cardiovascular disease remains the country’s leading cause of death, taking more Americans than all cancers combined. But for all its prevalence, heart disease’s risk factors aren’t clearly understood—and recent discoveries have called into question conventional wisdom on the subject. 

The model of cardiovascular disease popularized in recent decades has the ring of common sense: We eat fat, which clogs up our arteries like pipes in a house. But more and more the medical community is saying that’s just plain wrong. 

“It’s not as simple as just cholesterol in the diet raising cholesterol in the blood and causing plaque buildup,” says Donald Hensrud, a Mayo Clinic doctor who specializes in nutrition and disease prevention. “It’s much more complex.”

A comprehensive study published in 2014 collected data from more than half a million people and made conclusions that directly contradicted previous thinking. Among them: People who ate higher levels of saturated fat (meat, butter, cheese) didn’t suffer more heart disease than people who ate less. And counter to recent health theories, the study found no heart benefits from eating more “good” fats such as those in nuts, fish, and vegetable oils. 

On top of this are more studies that show the American approach to a “heart-healthy” diet of reducing everyday fat while replacing it with the starches and sugars that are delivered in high doses in processed foods (which we followed for decades in America, treating sugar mainly as a dental hazard) actually contributed to heart disease. 

University of Minnesota cardiologist Daniel Duprez stresses that, because research has been far from cut and dried, leading scientists make conclusions about heart disease only with caution. Diet, exercise, and smoking are major factors, yet so are autoimmune diseases, blood pressure, air pollution, diabetes, and genetic heredity. 

“It’s not as simple as just cholesterol in the diet raising cholesterol in the blood…”

Today’s major focus of research is the relationship between metabolic inflammation and heart disease, and the contributions to it made by refined sugar. Starches and sugars can exacerbate a state of inflammation in the body called metabolic syndrome, in which the body effectively reacts as though in a state of perpetual infection. 

This new emphasis is especially important in light of recent evidence that, in 1967, Harvard scientists who wrote a seminal paper downplaying the links between sugar and heart disease—while pointing a finger at animal fats—were paid by the sugar industry to pursue that conclusion. Their study influenced research and public policy for more than a generation—and the damage this corruption did to American health could take decades to reverse. 

Fortunately, there’s no controversy around some of today’s major tenets of understanding cardiovascular health, including the need for exercise and avoiding smoking. And while what we eat is enormously important, many in the medical field now say we should view diet in totality rather than fret about whether a single pat of butter will lead to the emergency room. 

Evidence suggests that consuming food in its whole, unprocessed form delivers the healthiest nutrition, mirroring the diet upon which we survived for many thousands of years before we learned to process sugar and meats or refine agricultural byproducts. Dr. Hensrud suggests a simple way to view a heart-healthy diet is by focusing on more plant-based foods while moderating animal foods (not necessarily cutting them out).

“Mother nature is pretty smart,” he says, “and puts nutritional concentrations in food in the way that our bodies can best utilize.”

“Look to the eating,” Dr. Duprez adds. “Here food is fast and it’s cheap, and you get so much of it that you have to take it home from the restaurant. People take more time in Europe, it’s more social, it’s more natural. I say look to the eating.”