A second important facet of a microbiota-friendly diet is to consume meat in limited quantities. Red meat contains the chemical L-carnitine, which certain microbes in the gut can convert to trimethylamine (TMA), which then gets oxidized into trimethylamine-N-oxide (TMAO). Regular meat-eaters have more TMAO than vegans or vegetarians. High levels of TMAO increase the risk of strokes, heart attacks,
