I'm replying twice because I hope I'm not giving anyone the wrong idea. Ornish is dead wrong, but he is not just pulling his philosophy out of thin air. He is cherishing his own published study over any further evidence that could possibly prove him wrong. It's become a matter of pride.

You see, Americans that eat the way Americans eat do in fact raise cholesterol levels by eating saturated fat along with their junk foods, carbs, white flour and sugar. The studies where these people are put on a low-fat diet naturally means they cut out french fries and donuts. The question is whether it was cutting out the saturated fats that lowered the cholesterol or cutting out the junk food carbs. Ornish thinks it was the saturated fats. I think they were just eating better all the way around.

As for the timidity of scientists to discredit other scientist's findings, Dr. Eades in PPLP showed this case in point, p. 46 [truncated]:

"Researchers studied a group of forty-three obese adults who had been unable to lose weight as outpatients...The higher carbohydrate group got their 1,000 calories at 115 grams of carbohydrate, 30 grams of fat, and 73 grams of protein. The low-carbohydrate group got about the same amount of protein, about double the amount of fat, and about a third less carbohydrate than the other group. After six weeks on 1,000 calories per day the higher-carbohydrate group had dropped their insulin levels by about 8 percent, the low-carbohydrate group dropped their insulin levels by a whopping 46 percent over the same period. Glucose, insulin, cholesterol and triglyceride concentrations decreased signifcantly in patients eating the 15 percent carbohydrate diet, but not so in the higher carbohydrate diet. We find it both interesting and telling that the authors chose to entitle the report of their study "Similar Weight Loss with a High- and Low-Carbohydrate Diet." The only result in these two groups that was similar was weight loss. In every other way, the low-carb group fared better. [The title was therefore very timid. And the authors of the study gave only this very timid conclusion:] it is "reasonable to question the advocacy of this [low-fat] dietary approach." Reasonable indeed!"

You see, even when studies suggest that low-carbing is better at lowering lipid levels, the authors of the studies are very reluctant to conclude that low-carbing is better than low-fat.