The study, which tracked 83,000 female nurses, was published in this week’s New England Journal of Medicine.
“It’s not that the two diets are equally good,” Harvard’s Thomas Halton said. “In fact, they’re both equally bad,” he said adding, “This is definitely an eye-opening study and it goes against a lot of what people think is common wisdom for nutrition.”
Some previous studies have shown that the Atkins diet, which is low in carbohydrates and high in fat and protein, increased the risk of heart disease.
The only diet that reduces the risk of the disease â€” and does so dramatically â€” is one where the fat and protein come from vegetable sources, the researchers found.
Women who showed a much lower rate of heart attacks tended to get their protein from beans, legumes, oatmeal, whole grain, tofu and brown rice, and their fat from nuts, olive oil and canola oil.
“They had a 30% reduction in the risk of heart disease over 20 years, which I find shocking,” Halton said. “You can get the positives of the low-fat diet and the positives of the low-carb diet, and none of the negatives.”
The reason that vegetable sources of protein and fat are so beneficial, he said, is that those foods produce a gradual increase in the blood sugar, not the rapid spikes generated by low-fat foods that are high in high in sugar.
“The way Americans are going low-fat is very unhealthy,” Halton said. “They have a very high glycemic load. They’re taking sugar. They’re taking white bread. They’re taking white rice and pasta. That certainly isn’t the answer.”
Although the study tracked female nurses, “the pathology of heart disease is not all that different in men and women,” Halton said.