What registered but unpublished clinical trials exist testing gelatin/collagen for weight management and what are their primary outcomes?

1. What trials are registered but lack published results

Public registry entries surfaced with direct relevance: NCT03357432 (titled around “Gelatin, Collagen, Gummy and PINP”), an oral collagen peptide supplementation trial NCT06321770, and a “Collagen Peptide Supplementation and Physical Exercise” trial NCT06240429 — all appear on ClinicalTrials.gov but the provided records contain no posted outcome results in the snippets, so they must be classed as registered yet unpublished in the reviewed material ^{[1] [2] [3]}.

2. What the registrations suggest about endpoints and intent

The registry titles and brief descriptions hint at biological and functional endpoints rather than definitive weight-loss trials: the gelatin/collagen gummy record references PINP (a procollagen type‑I biomarker), implying focus on collagen synthesis or tissue biomarkers rather than weight change per se ^[1], while the other two registrations combine collagen peptide dosing with exercise or with “active” peptides, suggesting primary outcomes like body composition, recovery or musculoskeletal metrics rather than calorie-regulation outcomes explicitly listed in the supplied snippets ^{[2] [3]}.

3. What published trials and reviews show about weight-related outcomes

Systematic reviews and a recent randomized trial landscape show collagen/gelatin research has assessed appetite, post‑exercise intake and body composition in small studies, with doses ranging (examples used in reviews) from about 5 g/day to 15 g/day and some trials measuring fat‑free mass or satiety rather than sustained weight loss ^[4]. A specific randomized trial on collagen peptides in females examined appetite and postexercise energy intake with a 15 g/day dose, but the supplied excerpt notes it did not measure key regulatory hormones and does not make bold claims of weight-loss efficacy in the snippet provided ^[5].

4. Primary outcomes — what can and cannot be said from available material

There is insufficient published data in the supplied reporting to state the registered trials’ primary numerical outcomes (weight change, BMI, fat mass) because the ClinicalTrials.gov snippets shown do not include completed results or outcome tables; therefore it is not possible, from the provided sources alone, to name trial-specific effect sizes or statistical conclusions for weight management ^{[1] [2] [3]}. Reviews and individual trial reports cited in the literature emphasize body composition, collagen biomarkers and satiety measures in small cohorts, and they warn about heterogeneity and methodological limitations that preclude strong weight‑loss claims ^{[4] [5]}.

5. Competing narratives and potential agendas

Industry and advocacy reporting that promotes collagen for broad metabolic or cosmetic effects is present in the landscape — trade summaries and industry-aligned updates highlight positive skin and joint outcomes and encourage product diversity (gummies, peptides), which can bias emphasis away from equivocal weight evidence ^[6]. Academic reviews counter that while short‑term satiety or biomarker changes exist, large, rigorous RCTs with weight loss as a predefined primary endpoint are lacking or unpublished in the materials reviewed ^{[4] [7]}.

6. Bottom line for readers and researchers

Registered trials exist that could provide data relevant to weight or body‑composition outcomes, but the materials supplied do not include published results for those registrations and systematic reviews caution that small, heterogeneous trials dominate the field; consequently, no definitive published trial‑level outcome on gelatin/collagen for weight management can be asserted from these sources alone ^{[1] [2] [3] [4] [5]}.