Liposomal glutathione solves the problem of poor absorption by packaging glutathione inside a liposome, a spherical lipid bilayer similar to human cell membranes
For instance, N-acetylcysteine (NAC), a precursor to GSH, has shown promise in increasing brain GSH levels and improving symptoms in first episode psychosis patients. NAC is so medically effective that it has been classified a medicine, hence not a food, and is no longer available over the counter in the US
doi: 10.1039/C5ME00004A
doi: 10.1016/j.pmpp.2015.09.001 31 HernndezL
However, you need to know the details and do your homework because glutathione is a finicky molecule, and not all forms are absorbable
GSTs catalyze the conjugation of acrolein to GSH and the corresponding conjugate is further modified by the enzymatic cleavage of the GSH glutamic acid and glycine residues by -glutamyltranspeptidase and cysteinylglycinase, respectively