The Wadsworth VA Hospital in Los Angeles operated a home where male army veterans resided. The meals were provided by one of two dining halls.
Men in dining Hall A continued their usual diet. The “saturated animal fat and hydrogenated shortening replaced with vegetable oils in the experimental diet” for the diets provided in dining Hall B. Low fat diets were not considered because such a diet required “gastronomic sacrifice”. The total fat content of the 2 diets were the same, providing 40% of the total energy. (Diets of 40% fat cannot be considered a healthy diet.)
This study is sometimes used to “proof” that a polyunsaturated fats promote cancer. A reading of papers from the trial shows that this is not the case.