Learning about nutrition is important, he agreed, but it can also fall by the wayside amid other demands. Medical school can be so stressful that, often, "our own eating habits are the first thing to go," he said.
Nutrition education is also slighted during fellowship training, the period after medical school when doctors specialize, said integrative preventive cardiologist Stephen Devries, executive director of the Gaples Institute for Integrative Cardiology in Deerfield, which advocates for nutrition and lifestyle interventions.
In the 32-page cardiology accreditation guidelines, "nutrition isn't mentioned once," said Devries, who is gathering support to lobby the Accreditation Council of Graduate Medical Education to mandate nutrition education as part of all physician training programs.
Today's primary care physicians spend less time than previous generations of doctors talking to patients about what they eat, according to a study published last year in the journal Medical Care.
Among the obstacles? "Many physicians are overweight themselves and may feel uncomfortable talking about healthy diet and physical activity when they themselves struggle with similar issues," said lead author Jennifer Kraschnewski, an assistant professor of medicine and public health sciences at the Penn State College of Medicine.
Though several diets can benefit heart health, a systematic review ranked the Mediterranean diet as the most likely model to provide protection against heart disease. The Lyon Diet Heart Study previously showed that it could reduce the risk of a second heart attack by up to 70 percent.
The traditional Mediterranean-style diet is characterized by high intake of olive oil, fruits, nuts, vegetables and cereals, moderate amounts of fish and poultry and low doses of dairy products, red and processed meat, and sweets. Consuming wine at meals in moderation, exercise and relaxing with friends are also considered important elements.
The heart-healthy mechanism is still a mystery, but evidence suggests the diet is anti-inflammatory and helps improve the function of endothelial cells, which pump out nitric oxide.
"Nitric oxide keeps cells within our blood vessels flowing smoothly, prevents inflammation from developing in the walls of the arteries, keeps us from getting stiff vessels and has a role in keeping us from developing blockages or plaque," said Dr. Caldwell B. Esselstyn Jr., author of "Prevent and Reverse Heart Disease."
"Certain foods compromise and injure the endothelial cells' capacity to make nitric oxide," Esselstyn said. "As we are constantly getting less and less nitric oxide, we are less able to prevent coronary artery disease."
Animal products, processed foods and sugar compromise the cells the most, said Esselstyn, who also, controversially, tells his patients to avoid oil.
For the recent study on the Mediterranean-style diet, published last month in the New England Journal of Medicine, researchers in Spain randomly divided patients who were already at high risk for heart disease into three groups. One was given a low-fat diet and advice on how to follow it.
The other two groups were placed on a Mediterranean diet, with one using at least four tablespoons of extra-virgin olive oil per day for cooking and dressing food. The third group was told to eat an ounce, or a generous handful, of a combination of walnuts, almonds and hazelnuts per day.
The volunteers in both Mediterranean diet groups had a "substantial reduction in the risk of major cardiovascular events among high-risk persons," the researchers concluded.
Yancy stressed that the results went beyond added olive oil, nuts or even regular wine consumption. "They were greatly influenced by diet coaching and constant reinforcement that kept patients on board with the chosen diet," he said. "It's the entire diet program. That's where the real gains reside."
For Jessie Chavez, 39, a software engineer for Google, heart disease loomed in his future. His father had three heart attacks — the third was fatal — and Chavez, who worked long hours at the computer and neglected his diet, had high cholesterol.
Initially his doctor put him on a statin drug. But when he asked if there was anything more he could do, "she said, 'Well, of course you can look into diet,' but I felt like she didn't see it as something viable," Chavez said.
Chavez went to see Devries, who incorporated a Mediterranean-style diet and exercise into his heart health program. Chavez, 5 feet 10 inches tall, dropped his weight from 196 to 156 and is now off nearly all medication because his cholesterol is back to normal. Once physically unfit, he's now able to run 10 miles.
"As an engineer, I always think, 'Where's the proof?'" said Chavez, of Berwyn. "To actually have a cardiologist tell you, 'Here are a few studies, this is what it shows and this is the impact' gives you more options. I liked knowing it wasn't part of a fad, but science."