Metabolomics of carnitine metabolism in participants with phenylketonuria with the use of AA-MFs and GMP-MFs. Values for dietary intakes of carnitine (A) and choline (B) are means ± SEMs and are based on 3-d food records; n = 30/treatment group. Values are scaled intensity means ± SEMs for plasma deoxycarnitine (C), carnitine (D), and choline (E); PKU, n = 10/treatment group; control group, n = 15. Values are scaled intensity means ± SEMs for urinary deoxycarnitine (F), carnitine (G), and TMAO (H); n = 9/treatment group. Labeled means without a common letter differ, P < 0.05. AA-MF, amino acid medical foods; GMP-MF, glycomacropeptide medical foods; PKU, phenylketonuria; TMAO, trimethylamine N-oxide.