The impact of collagen protein ingestion on musculoskeletal connective tissue remodeling: a narrative review

Holwerda AM, van Loon LJC · Nutrition Reviews

Concludes collagen's glycine/proline content plausibly supplies precursors for connective-tissue synthesis, but that direct evidence collagen ingestion increases connective-tissue protein synthesis in humans remains unclear and largely biomarker-based: the one in-vivo human measurement found collagen peptides no better than whey, and the fat-free-mass gains in two training trials are called unrealistic.

Population

Narrative review of human collagen/gelatin ingestion studies

Limitations

Narrative (not systematic) review; the evidence base itself is small and surrogate-heavy. Both authors received funding from PB Leiner, a collagen manufacturer within Tessenderlo Group, to study dietary collagen; they declare no relevant interests.