The founding metabolic-ward dose-response result: under tightly controlled feeding, adding dietary cholesterol raises serum cholesterol, and the raw comparisons already show the effect flattening at higher intakes (the basis for fitting a square-root rather than linear form). Full text was not retrieved (1965, paywalled); the finding is extracted from the source’s step-2 summary and is among the most independently corroborated results in nutrition (Clarke 1997 meta-analysis of 395 experiments).
Methodology
Part II of the Keys/Anderson/Grande metabolic-ward series: controlled feeding in healthy men (~22 per arm at Minnesota) across dietary-cholesterol intakes of ~50-1450 mg/day, pooled with comparable data from four other institutions; the founding dose-response equation is a least-squares fit over 19 dietary-cholesterol comparisons. (Full text not retrieved — 1965, paywalled; extracted from the step-2 summary plus the corroborated equation form.)
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