GHK Cu vs NAD+: Which Longevity Peptide Should You Take or Stack? GHK Cu may Prevent Oxidative Stress in Skin by Regulating Copper and Modifying Expression of Numerous Antioxidant Genes NAD+ with GHK Cu IONTOPHORESIS PUSH PATCH THERAPY GHK Cu vs NAD+: Which Longevity Peptide Should You Take or Stack? Two power players. Very different roles. Let's talk NAD+ vs. GHK Cu NAD+ works behind the scenessupporting cellular energy, metabolic function, brain clarity, and overall longevity. Think internal optimization, from the inside