Glycine is the simplest amino acid and a building block for proteins. Your body makes it, but sometimes not enough, so adding more through supplementation can help. It also works as a brain messenger and forms a major part of collagen.
People take glycine before bed to fall asleep faster and get deeper rest. It helps by lowering body temperature and quieting brain activity. This same calming effect on the nervous system supports a relaxed mood and eases everyday tension.
As a main ingredient in collagen, glycine aids joint comfort and skin firmness. The body also uses it to make creatine and glutathione, two compounds that speed workout recovery and protect cells. You can buy it as a slightly sweet powder that stirs easily into water or any drink. A common bedtime dose runs from 3 to 5 grams.
Most people handle typical doses without trouble. Large amounts can sometimes cause loose stools or mild stomach upset. Talk to a doctor before using glycine if you take sedatives or antipsychotic medications, since the combination might be too strong.