Evidence snapshot: The strongest human evidence comes from a 2-year randomized controlled trial in 65 healthy older adults (Nass et al., 2008, Annals of Internal Medicine) showing sustained GH/IGF-1 increases and preserved fat-free mass, plus an earlier short-term human polysomnography study on sleep (Copinschi et al., 1997, Neuroendocrinology, PMID 9349662)
Injectable L-carnitine can support weight loss through several mechanisms related to its role in fatty acid metabolism and energy production
GHK-Cu (sister peptide) given as repeated 2 mg injections into rat wound chambers modulated decorin/biglycan and increased type-I collagen and GAGs grounds the milligram-per-injection magnitude sometimes cited for the class, but this is GHK-Cu, rat, wound-healing
Metabolic Brain Dis 2002;17:183-197
Several homemade options work well: Black coffee or green tea: Free caffeine, zero calories, mild thermogenic effect