Sarcosine, also known as N-methylglycine, is a metabolite of glycine. It shares properties with both glycine and D-serine, though its effects are weaker. Sarcosine supplementation can be used to alleviate symptoms of depression and schizophrenia, or improve cognition. It is absorbed more reliably by the body than D-serine, which can also treat similar conditions. Sarcosine is being investigated for its connection to prostate cancer. It may be a biomarker for prostate cancer, which means that if sarcosine levels in the blood are higher than normal, it could be an indicator of prostate cancer. This doesn’t mean that sarcosine itself causes cancer. More research is needed to confirm this relationship. Sarcosine’s main mechanism involves inhibiting a transporter, called GlyT1, which takes up glycine and D-serine into cells. This increases the levels of glycine and D-serine in the body and increases their effects. Sarcosine, a glycine transporter type 1 inhibitor and an N-methyl-D-aspartate (NMDA) receptor co-agonist at the glycine binding site, potentiates NMDA receptor function. Sarcosine is an inhibitory glycine receptor agonist.