10
Why Can’t I Have “Heart Healthy” Oils?
DURING THE 1990s, the headlines were suddenly filled with the wonders of “the Mediterranean Diet.” It was widely hailed as a much more heart-healthy approach to eating than the average American diet, largely on the basis of research by a group of French scientists headed by Dr. Michel de Lorgeril of Joseph Fourier University in Grenoble.1 Known as the Lyon Diet Heart Study, the research spawned scores of magazine and newspaper articles and Mediterranean-style cookbooks.
For this study, the French researchers assembled 605 subjects—all of whom had survived a first heart attack—and divided them into two groups. The profiles of the two were very similar when it came to risk factors for coronary artery disease, including cholesterol and other blood lipid levels, blood pressure, and tobacco use.
About half of the subjects—302—were asked to consume a Mediterranean-style diet, which the American Heart Association defines as follows:
 
Participants in this group agreed to consume a diet that averaged 30 percent of daily calories from fat—8 percent from saturated fat, 13 percent from monounsaturated fat, 5 percent from polyunsaturated fat—and just 203 milligrams a day of cholesterol.
The other participants in the study, 303 people in all, functioned as a control group, and were given no particular dietary advice beyond being asked by their physicians to eat prudently. On average, they ate a diet that the American Heart Association describes as “comparable to what is typically consumed in the United States.” It derived about 34 percent of its calories from fat—12 percent from saturated fat, 11 percent from monounsaturated fat, and 6 percent from polyunsaturated fat—and included about 312 milligrams a day of cholesterol.
After a little more than a year, the researchers noted that those following the Mediterranean-style diet were doing much better than the control group. The results, they reported, were “striking.” After nearly four years, the results were clearer than ever. Those on the experimental diet were 50 to 70 percent less likely to experience all the cardiac ailments the researchers recorded, from minor events that required hospitalization to major emergencies such as angina, stroke, or heart failure, to heart attacks and even death.
Impressive results. It is not surprising that they received such great attention and that the Mediterranean diet attracted many adherents. And it is also not surprising that many of my patients are at first puzzled by the fact that my nutrition plan does not permit monounsaturated oils such as olive oil or canola oil to be part of an arrest and reversal program for coronary artery disease. Because of the Lyon Diet Heart Study, the media have taken to referring to these oils as “heart healthy.”
Well, nothing could be further from the truth. They are not heart healthy. Between 14 and 17 percent of olive oil is saturated, artery-clogging fat—every bit as aggressive in promoting heart disease as the saturated fat in roast beef. And even though a Mediterranean-style diet that allows such oils may slow the rate of progression of coronary artery disease, when compared with diets even higher in saturated fat, it does not arrest the disease and reverse its effects.
Dr. Walter Willett, a professor of public health at Harvard, has written a book touting the benefits of monounsaturated oil. Recently, when he was lecturing in Cleveland, I asked whether he had seen any evidence that a diet rich in monounsaturated oils has arrested and reversed coronary artery disease. No, he replied—but added that there was indirect evidence of arrest and reversal in the Lyon Diet Heart Study.
But let’s take another look at that study. There is no question that the group consuming the Mediterranean-style diet did not fare nearly as badly as those in the control group. But there is another way to look at the results of the Lyon Diet Heart Study. By the end of the study, nearly four years after its start, fully 25 percent of the subjects on the Mediterranean diet—one out of four—had either died or experienced some new cardiovascular event.
I feel these are wretched results for a nonmalignant disease. We can do much better. During a panel discussion at the 2nd National Summit on Cholesterol and Coronary Artery Disease, in 1997, Colin Campbell, author of the best-selling China Study, was asked his thoughts on the results of the Lyon Diet Heart Study, and to compare those results with those he found in studying health and nutrition in rural China, where coronary disease is practically nonexistent. Colin didn’t hesitate for a moment. The Mediterranean and rural Chinese diets are practically the same, he replied. “I would say the absence of oil in the rural Chinese diet is the reason for their superior success.”
In fact, the medical literature is filled with evidence of the harmful effects of monounsaturated oil. The late Dr. David H. Blankenhorn of the University of Southern California School of Medicine compared baseline angiograms with one-year follow-up angiograms in persons with coronary artery disease. He found that the disease had progressed just as much in those consuming monounsaturated fats as it had in those eating saturated fat.2
Similarly, Lawrence Rudel of the Wake Forest University Baptist Medical Center experimented with the diet of the African Green monkey, which metabolizes fats very similarly to human beings. At the end of five years, he found that those monkeys consuming monounsaturated fat did show higher levels of HDL (good) cholesterol and lower levels of LDL (bad) cholesterol, but autopsies on them showed that they had developed just as much coronary disease as those fed saturated fat.3 Rudel later repeated the experiment using rodents and obtained the same result.
Robert Vogel, the University of Maryland School of Medicine researcher whose experiments I recounted in Chapter 5, found that eating bread dipped in olive oil reduced the dilation in the brachial (forearm) artery that is normally seen with the brachial artery tourniquet test.4 This suggested temporary injury to the endothelial cells, compromising their ability to produce nitric oxide. And Japanese researchers have shown that monounsaturated fat elevated blood sugar and triglycerides in rodents with a diabetic tendency.5
And once again, I invoke my own experience. In the summer of 2004, I had a call from the Reverend William Valentine of North Carolina. In 1990, he had undergone a quintuple coronary bypass. Since that surgery, he had been carefully following a plant-based nutrition program. His weight had fallen from 210 pounds to a trim 156, which he had maintained over the years. But by mid-2004, he was experiencing a recurrence of angina, especially when he exercised, and sometimes even while resting.
He had read about my program in a health newsletter, and he wanted my advice. He was extremely anxious about undergoing any repeat bypass surgery or intervention, and wanted very much to avoid it. But he couldn’t imagine what more he could do, on his own, to curb the angina. And since he was eating whole grains, legumes, vegetables, and fruit, I was initially baffled.
At a loss for suggestions, I asked the Reverend Valentine to tell me, once again, everything he was eating, and to leave out absolutely nothing. This time, he added to the list. He had forgotten, he said, to mention that he was consuming “heart healthy” olive oil at every lunch and dinner and in salads.
It was what they call a Eureka moment. Immediately, I advised him to give up the olive oil. He did—and within seven weeks, his angina had completely disappeared.