A Nature Scientific Reports 2016 study showed GHK-Cu had no cytotoxicity to human keratinocytes at concentrations up to 5,800 M over 72 hours and did NOT induce inflammatory biomarkers (IL-1, IL-8, HSPA1A, FOSL1) unlike other copper compounds, concluding GHK-Cu has a low potential of inducing skin irritation
yet, it remains a double-edged sword, as chronic high levels are notorious for promoting cachexia(2)the severe muscle wasting often seen in late-stage cancer
Possible causes include pregnancy, excessive caloric restriction, body fat dropping below the threshold for menstruation (typically 18% to 20%), or changes in ovulation timing
V.BezrukovL.GawrischK.ZimmerbergJ
Lactobacillus Salivarius REN Inhibits Rat Oral Cancer Induced by 4-Nitroquioline 1-Oxide
The real question is not whether these drugs work