glutathione gout Liquid Supplement, Lemon Berry Flavored Acerola Energy Booster w/Zinc, Daily Vitamins & Minerals, Zero Sugar Formulation, Everyday Auto-Immune Support for Adults, 0.34 fl oz, Pack of 60 : Health & A review of the evidence

The liposomal delivery system in that 2016 study and Pickart's squalane approach are solving the same problem through different means: getting GHK-Cu where it needs to go

10.1038/nrurol.2017.98 62

Measurements of UV-generated free radicals/reactive oxygen species (ROS) in skin

Enhanced synaptic plasticity in newly generated granule cells of the adult hippocampus

Possibilities include: fecal SCFA levels (as an indicator of beneficial fermentation), serum TMAO (marker of detrimental microbial metabolism), gut permeability assays (like urinary sugar tests or blood zonulin) to gauge gut barrier integrity, and even gut microbial gene profiles that might predict rapid vs slow disease progression

You're not just drinking a beverage