> I've heard recently that the causality for heart disease actually goes the opposite way than everyone assumed.
This "Assumption" would be a good case study of the infection of common knowledge with charlatanism.
Better scientists than Ancel Keys already knew that polyunsaturated oils were not appropriate for human consumption. Soybean oil and Linseed oil were used to make paint & stain, because they're good 'drying oils'.
But Dr. Key's theory was picked up by the mass media and used to demonize butter, and to promote garbage like "I Can't Believe It's Not Butter"...
People are easy to swindle.