A photo taken in bathroom fluorescent light at 7am versus one taken in golden-hour window light at 5pm will make anyone's skin look "transformed" regardless of what product they used
It is legally sold in over-the-counter cosmetics (which do not require FDA pre-approval), but injectable GHK-Cu is an unregulated research chemical
Tretinoin is prescription-only in the US, UK, Canada, and most markets
Glutathione is compartmentalized throughout the cell, with 80-85% in the cytosol, 10-15% in mitochondria, and smaller amounts in the endoplasmic reticulum, nucleus, and peroxisomes
It suggests the company has experience working with the types of delivery systems, textures, and packaging formats that serum products require
Natural levels of glutathione tend to decline as we age