Abstract: Trimethylamine N-oxide (TMAO) is an intestinal flora metabolite produced in the liver by the oxidation of trimethylamine (TMA) by hepatic enzymes. Recently, it has been found that plasma TMAO levels play an important role in the development and progression of osteoporosis. This review has presented the physiological functions and metabolic processes of TMAO, and its effects on the development and progression of osteoporosis through oxidative stress and inflammation. Plasma TMAO levels are influenced by diet as well as medications, which provides a new perspective and target for the treatment and prevention of osteoporosis.

Key words: trimethylamine N-oxide, intestinal flora, osteoporosis, bone mineral density, fracture