Capacity of Human Intestine to Absorb Exogenous Cholesterol

Studies on the influence of dietary cholesterol on cholesterol metabolism in the isotopic steady state in man.

“…In both studies maximal dilution of the specific activity was obtained in the duodenal aspirate, and this specific activity was in each instance almost equal to that of the serum; in the subject on the low cholesterol intake (Subject B), the specific activity remained virtually unchanged throughout the remainder of the gastrointestinal tract; in this individual cholesterol turnover (0.74 g per day) enormously exceeded cholesterol intake (0.08 g per day), and it may be concluded that complete mixing and dilution occurred by the time bile mixed with the exogenous sterol. This is certainly not (19) and differ markedly from earlier estimates of this capacity at 1 to 3 g per day (22)(23)(24). The actual direct estimation of this capacity in an intact organism can best be made by use of a double isotopic steady state (13).…”

The Intestinal Absorption of Dietary Cholesterol by Hypercholesterolemic (Type II) and Normocholesterolemic Humans

“…A similar phenomenon was found in the rat (27). In an earlier study, Karvinen, Lin, and Ivy measured the cholesterol absorption of the subjects fed cholesterol in the amounts of 1, 3, 6, and 9 g/day by the balance technique (28). They found that the average maximum intestinal capacity of their subjects to absorb cholesterol was 2.0 g/day.…”

Effect of diet and exercise on atherosclerosis in the goat

“…Several experiments (32)(33)(34) appear to demonstrate a hepatic feedback mechanism; Dietschy and Gamel (35) propose a feedback mechanism for intestinal synthesis. But, according to some authors, man's relatively constant day to day plasma cholesterol level is due to a limited ability of the intestine to absorb exogenous cholesterol rather than to feedback, ttyant (21), Kaplan (30) and Taylor (36) suggest an absorption maximum of 300 to 300 mg of cholesterol per day, while Karvinen et al (37) suggest 2 to 3 g per day. In the Masai of East Africa, a negative feedback of dietary cholesterol on hepatic synthesis has been well uêmÛMBLLÛLêu {38.391, but Liiê Hâââl ûûpcât lO uc âulë tO âuSûrb mûïc cholesterol than can Americans.…”