A 2016 comparative study published in Nature Scientific Reports directly compared copper compounds and found GHK-Cu non-cytotoxic across all tested concentrations up to 5,800 micromolar over 72 hours
Guo YW, Zhang X, Zhou, et al
It removes impurities and adds shine to the skin
Indeed, murine studies and recent clinical trials have indicated the potential health benefits of selenium supplementation for improving the quality of life and reducing the side effects following organ-specific radiotherapy [61, 62, 95,96,97,98,99]
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