DMV International has added Cysteine Peptide to its range of bioactive ingredients. Cysteine Peptide, which is a natural milk ingredient, is meant to help increase energy, motivation and promote better sleep. According to the company, as people age, the body produces less glutathione, which is needed to break down toxic substances such as alcohol and stimulants. Cysteine Peptide, a whey protein hydrolysate, allows the body to synthesize glutathione. Cysteine Peptide, through the production of glutathione in the liver, helps break down these toxic substances.