Endpoint: surrogate — postprandial + short-term plasma/urinary TMAO across a controlled feeding period.
Randomized crossover trial in 40 healthy young men fed isonitrogenous test meals of fish, egg, red meat, or a fruit control. Fish produced 46-62-fold higher circulating and urinary TMAO than eggs, meat, or the fruit control; the magnitude of response also depended on individual gut-microbiota composition.
relevance_note: the key “eggs are a minor TMAO source next to fish” skeptical anchor — habitual fish consumption (associated with LOWER CVD risk in most cohorts) raises TMAO far more than eggs do, directly undercutting a simple “TMAO dose from diet predicts CVD harm” reading of the pathway.