Classify peptides relevant to body composition—including incretin-based medicines and growth-hormone-axis agents—and distinguish endogenous peptides, approved peptide medicines, unapproved “research peptides,” anabolic steroids, and protein supplements.

Explain how incretin-based medicines and growth-hormone-axis peptides can affect appetite, energy intake, energy expenditure, and tissue growth, distinguishing demonstrated mechanisms from common “metabolic boost” claims.

Evaluate the human evidence for effects on body weight, fat mass, and lean mass alongside common adverse effects, serious risks, and key safety uncertainties for incretin-based medicines and growth-hormone-axis peptides.