Theoretically, yes. Certain groups of people (such as older adults) can have both reduced glutathione levels and reduced cysteine and glycine levels.[1] Although both glycine and cysteine can be produced by the body, their levels seem to be highly influenced by diet, and it’s possible that endogenous production of these amino acids may not be sufficient in people with higher demand (such as people with high levels of oxidative stress).[2][3]
References
- ^Sekhar RV, Patel SG, Guthikonda AP, Reid M, Balasubramanyam A, Taffet GE, Jahoor FDeficient synthesis of glutathione underlies oxidative stress in aging and can be corrected by dietary cysteine and glycine supplementationAm J Clin Nutr.(2011 Sep)
- ^Meléndez-Hevia E, De Paz-Lugo P, Cornish-Bowden A, Cárdenas MLA weak link in metabolism: the metabolic capacity for glycine biosynthesis does not satisfy the need for collagen synthesisJ Biosci.(2009 Dec)
- ^Gersovitz M, Bier D, Matthews D, Udall J, Munro HN, Young VRDynamic aspects of whole body glycine metabolism: influence of protein intake in young adult and elderly malesMetabolism.(1980 Oct)