While I don't have studies on hand, I recommend watching `Viva Longevity!` on YouTube. He makes a case for the Ancel Keys studies, and why saturated fat is bad and why fiber is good.

It's been nearly a year or two since I've looked into it, but basically there is a lot of money in marketing for the beef and dairy industries, and that includes lobbying and influencing the outcomes of scientific studies. It's worth scrutinising claims against the Ancel Keys studies soley based on the fact, in my opinion.