O-103 - Egg ingestion raised plasma and urine TMAO dose-dependently, with ~11-15% of egg choline converted to TMAO (n=6)
Urinary TMAO ran 236, 433, 634, 944, 900 umol/24h across 0/1/2/4/6 yolks. Direct demonstration that egg choline feeds the TMAO pathway in humans.
Link to originalMethodology
Longitudinal, double-blind, randomized dietary intervention in 6 volunteers, each fed breakfast doses of 0, 1, 2, 4, or 6 egg yolks (crossover, every subject received all 5 doses, >2-week washout between doses) on a standardized low-choline background the day before and day of each dose. Plasma TMAO was sampled before and at intervals up to 24 h after each dose (peak ~6-8 h); 24-h urine TMAO, pre- and 24-h-post serum hsCRP, and plasma oxidized LDL were also measured. NIDDK-funded (Zeisel choline lab; grants DK56350, P30 DK034987). Full text via PMC (PMC4135488). PMID 24944063; AJCN 2014;100(3):778-786.
Link to original
Why this is evidence
Egg choline is converted to TMAO dose-dependently in humans, giving a non-cholesterol egg component with a plausible atherogenic route — the ‘other operative exposure’ H-54 posits. H-26/H-3 attribute egg’s effect to cholesterol/fat, not choline, so this discriminates H-54 from both.