Even cardiologists recognize the lack of evidence in present guidelines

http://cardiobrief.org/2017/02/27/top-cardiologist-blasts-nutrition-guidelines/

“Why did we go wrong? We went wrong because of surrogate endpoints.”

The demonization of fats— saturated fats in particular— stemmed from earlier observations linking saturated fat consumption to LDL levels. Yusuf reported that PURE confirmed this finding, but he also noted that the overall difference in LDL was small and that there was a large amount of variance. More importantly, randomized studies that have looked at fat reduction to reduce cardiovascular events have not shown benefit, except in cases where fat levels were extremely high, he said.

Yusuf said that the ApoB/ApoA ratio is a much more highly sensitive marker of risk. Data from PURE shows that this ratio goes up with carbohydrate consumption but is neutral with saturated fats or polyunsaturated fats and declines with monounsaturated fats.