The diet-heart hypothesis promoted by Ancel Keys was based on bad science, cherry-picked data, and gross generalisations. The saturated fat used in his experiments was vegetable oil (margarine) and he extrapolated the results to animal fat.

The current theory is that heart disease is caused by vegetable oil and sugar.

The Paleo and keto enthusiasts demonize Keys as the root cause of the western world's obesity problem.

For books, try

    * "Good calories, bad calories" - Gary Taubes
    * The Paleo Solution - Robb Wolf