Tissue levels and optimum dosage of vitamin C in guinea pigs.

Ascorbic acid mixed with the diet of guinea pigs achieved substantially higher maximum tissue concentrations of ascorbate than when ascorbic acid was administered orally once a day. A 0.5% w/w of ascorbic acid in the diet ensured a state close to maximal tissue steady-state levels of ascorbate. In guinea pigs fed a diet with a high content of saturated fatty acids or with 0.2% w/w of cholesterol, the highest rate of cholesterol transformation into bile acids and the lowest concentration of total lipids, cholesterol and triglycerides in blood serum and liver were found in the group fed a diet with 0.5% w/w of ascorbic acid as compared to the marginal-deficiency group and the group receiving 0.05% w/w of ascorbic acid in the diet. Maximal tissue steady-state levels of vitamin C are probably optimal for the guinea pigs' health.