Absorption of cholesterol oxidation products from ordinary foodstuff in humans.

BACKGROUND Information on the absorption of cholesterol oxidation products (COP) from ordinary foodstuff in humans is scarce. METHODS Five healthy young men were offered a salami- and Parmesan-containing meal naturally rich in COP. Plasma and lipoprotein COP concentrations were measured over the following 9 h. RESULTS The mean plasma free (nonesterified) COP concentration showed its maximal increase 3 and 5 h after meal consumption. In contrast, the raise in plasma total COP concentration began 6 h after the meal with a maximum at 8 h and was statistically significant for 7alpha- and 7beta-hydroxycholesterol and 7-ketocholesterol. The increase in plasma total cholesterol concentration was comparable to that of total COP. Comparing the COP composition of the chylomicrons and the test meal, cholestanetriol, 7-ketocholesterol, and to a lesser extent cholesterol-alpha-epoxide were underrepresented in the chylomicrons as was the opposite for 7beta-hydroxycholesterol. In very-low-density lipoprotein, a steady increase in the COP:cholesterol ratio was observed from 6 h on. CONCLUSION COP from ordinary foodstuff were absorbed in the human intestinal tract but differences in the bioavailability of the single COP compounds were found.