[cyphar]

The anti-fat push in the last few decades was the result of the sugar lobby actively pushing pseudoscience to argue that fats were responsible for the rising rates of heart disease rather than sugar[1]. This is somewhat reminiscent of the "science" funded by the tobacco lobby.

Ironically, margarine was arguably worse for your health than butter because it contained transfats (a side effect of the hydrogenation process on oil) which are now known to definitely cause heart disease[2]. In fact the link is so clear that a 2006 review flatly stated that "on a per-calorie basis, trans fats appear to increase the risk of [coronary heart disease] more than any other micronutrient"[3].

[1]: https://www.npr.org/sections/thetwo-way/2016/09/13/493739074... [2]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3955571/ [3]: https://www.nejm.org/doi/full/10.1056/NEJMra054035