There are several conditions that glycine supplements are claimed to treat, including schizophrenia, strokes, and memory problems. However, some of these uses have more scientific validity than others. As an amino acid, glycine works by building proteins and by stimulating certain receptors in the brain. It is not known if glycine is beneficial or safe for use in children, other than through normal dietary means.
Glycine is an amino acid. Because the human body can produce glycine on its own, glycine is not essential for human nutrition (it is not an "essential" amino acid). However, supplementation is often claimed to be beneficial for the following conditions:
- Strokes (to minimize damage after a stroke)
- Memory problems
- An enlarged prostate (known medically as benign prostatic hyperplasia, or BPH)
- 3-phosphoglycerate dehydrogenase deficiency, a rare genetic condition
- Isovaleric acidemia, also a rare genetic condition
- Leg ulcers (when applied to the skin).
Sometimes glycine is also claimed to help protect the liver and kidneys and to help prevent cancer.
Some of these claims may have some scientific evidence in their favor, while others have absolutely no scientific basis (see Does Glycine Work? for more information). As with many supplements, claims for the benefits of glycine are sometimes exaggerated, and such claims must be evaluated critically. Most importantly, it is essential to remember that natural products should not be used carelessly, as many natural products can be quite toxic (for instance, many poisons are natural products).
How Does Glycine Work?
Glycine is an amino acid, which is important for building proteins. For most people, the body can make its own glycine, although glycine is also found in protein-rich foods.
In addition to its use as a building block for making proteins, glycine also works as a neurotransmitter in the brain, stimulating NMDA receptors. "NMDA" stands for N-methyl-D-aspartate. It is thought that some of the symptoms of schizophrenia may be related to problems with NMDA receptors.