ghk-cu hair growth clinical trial humans randomized double blind Healthy-looking starts where most people never GHK-Cu Peptide for Hair Growth:

Researchers analyzing body composition data have noted not only greater overall weight reduction but also a favorable ratio of fat loss to lean mass preservation, consistent with the hypothesized energy-expenditure component

Preliminary research and animal studies suggest that Body Protection Compound 157 may support muscle growth by promoting cell proliferation, enhancing muscle and tendon healing, and improving blood flow to injuries

Heart palpitations and caffeine sensitivity would mean the person benefits from eating caffeine-free stuff

Hossain and Komatsu, 2013)

The idea is to verify safety (and efficacy) without the cloud of bias that internal testing could introduce