Figure 2: Regression and 95% CI of oral dose and urinary excretion of vitamin B1 (A), vitamin B2 (B), vitamin B6 (C), niacin (D), pantothenic acid (E), folate (F), biotin (G) and vitamin C (H) [23]. Values are individual points of six subjects in each dose. 4-PIC signifies 4-pyridoxic acid, a catabolite of vitamin B6 vitamers, the Nam metabolites does the total amount of nicotinamide metabolites, MNA, 2-Py and 4-Py, the PaA does pantothenic acid, and the AsA does ascorbic acid.