Classic formula-diet metabolic-ward trial: 56 adult men fed a cholesterol-free baseline formula diet for 3 weeks, then divided into 4 groups of 14 receiving 0, 106, 212, or 317 mg cholesterol per 1000 kcal for 6 weeks, with background fat composition fixed near the typical US diet (~40% saturated, ~12% polyunsaturated). Each 100 mg/1000 kcal increment in dietary cholesterol raised serum cholesterol by ~12 mg/dL. One of the primary datasets underlying the Keys/Hegsted-type dose-response equations. relevance_note: A tightly controlled formula-diet metabolic-ward primary quantifying the average dietary-cholesterol → serum-cholesterol slope, from a study group with an industrial (non-egg) COI worth flagging.