From the Manufacturer:
"Glycine along with cysteine have the ability to stimulate glutathione synthesis in the body. Glutathione is an important constituant in antioxidant and detoxification systems in all living things. Glycine's ability to stimulate glutathione production make it important in supporting healthy hepatic and kidney function. Glycine is an inhibitory neurotransmitter and is also involved in the production of DNA.
Kirkman Glycine capsules are part of the Hypoallergenic line and contains only glycine and plant cellulose. No other additives are present."