Tier 2 — strong

A calcium-collagen chelate dietary supplement attenuates bone loss in postmenopausal women with osteopenia: a randomized controlled trial

Marcus L. Elam, Sarah A. Johnson, Shirin Hooshmand, Rafaela G. Feresin, Mark E. Payton, Jennifer Gu, Bahram H. Arjmandi

Journal of Medicinal Food 2015 18(3):324–331

Bibliography

DOI: 10.1089/jmf.2014.0100
PubMed: PMID 25314004
Funding: Funding statement (verbatim): "The funding and calcium-collagen chelate supplement (KoAct®) were provided by AIDP, Inc. (City of Industry, CA, USA)."
Competing interests: No explicit competing interests statement in the paper. Co-author Jennifer Gu is affiliated with AIDP, Inc. — the commercial manufacturer of the KoAct® calcium-collagen chelate product tested in this study and the entity that both funded the trial and supplied the test material. Remaining co-authors are academic (Florida State University, San Diego State University, Oklahoma State University). Substantial commercial conflict of interest across product supply, funding, and one author's affiliation.

Study snapshot

Design	Randomised, double-blind, active-controlled (calcium + vitamin D vs calcium-collagen chelate) parallel-group trial
Model	Postmenopausal women with DXA-confirmed osteopenia
Sample	39 randomised (20 CC group, 19 control); intention-to-treat analysis on all randomised
Intervention	5 g/day calcium-collagen chelate (KoAct®, containing 500 mg elemental calcium + 200 IU vitamin D3) versus control (500 mg elemental calcium + 200 IU vitamin D3), once daily for 12 months
Duration	12 months; DXA at baseline, 6 months, 12 months; blood biomarkers at baseline, 6, 12 months
Endpoints	Whole-body BMD change at 12 months by DXA; Lumbar spine BMD change; Hip BMD change; Serum sclerostin; Serum TRAP5b; Serum bone-specific alkaline phosphatase (BAP); BAP/TRAP5b ratio

What the study showed, in plain terms

After menopause, women lose bone density rapidly because the drop in oestrogen removes one of the body's main brakes on bone breakdown. Standard prescriptions for slowing this loss — bisphosphonate drugs — work well but many women can't tolerate them or prefer to avoid pharmaceuticals. Calcium and vitamin D supplements are the go-to alternative, but on their own they only partly slow the bone loss.

This trial tested whether adding collagen peptides to calcium and vitamin D could do more than calcium and vitamin D alone. Thirty-nine postmenopausal women with mild bone loss (osteopenia) were randomly assigned to take either the combined calcium-collagen product or a plain calcium plus vitamin D control every day for a year. Bone density was measured at the start, halfway through, and at the end using a DXA scan, and blood tests tracked markers of bone breakdown and rebuilding.

The women taking the collagen-containing product lost noticeably less whole-body bone density over the year — about 1.3 percent versus 3.75 percent in the control group. Blood markers also shifted in a favourable direction: bone-breakdown signals dropped more in the collagen group, and the ratio of bone-building to bone-breakdown markers improved. The trial is small — only 39 women — so the results need larger confirmation, but combined with the König 2018 and Zdzieblik 2021 postmenopausal bone trials, they form a coherent signal that collagen peptides added to standard bone nutrition may meaningfully slow bone loss in this population.

Key findings

Whole-body BMD loss at 12 months was significantly attenuated in the calcium-collagen chelate group compared with control: −1.33% vs −3.75% in completers analysis (p = 0.026); −0.33% vs −2.17% in intention-to-treat analysis (p = 0.035).
Serum sclerostin (bone-resorption inhibitor marker) was significantly reduced in the CC group vs control (p < 0.05) at 6 months.
Serum tartrate-resistant acid phosphatase isoform 5b (TRAP5b, marker of osteoclast activity) was significantly reduced in the CC group vs control (p < 0.05) at 6 months.
The bone-specific alkaline phosphatase to TRAP5b ratio (BAP/TRAP5b — an indicator of bone-formation vs bone-resorption balance) was significantly higher in the CC group vs control (p < 0.05) at 6 months.
Lumbar and hip BMD trends favoured the CC group but did not reach statistical significance individually — the primary effect was on whole-body BMD.
No treatment-related adverse events reported.

What this study can and cannot tell us

Small sample size (n = 39 randomised, ~20 per arm) — confidence intervals are wide and results require replication in larger trials.
Both arms received calcium plus vitamin D — the trial does not isolate the effect of collagen alone against a true placebo. The demonstrated benefit is "collagen chelate added to calcium+D" vs "calcium+D alone."
Single dose (5 g/day chelate) tested — no dose-response established.
Substantial commercial conflict of interest — trial funded by AIDP Inc., co-author Jennifer Gu is an AIDP employee, and KoAct® is an AIDP proprietary product.
Female-only, US-based, ethnicity not detailed — external validity to other populations not directly established.
Study characterised as long-term extension of a prior 3-month intervention by the same group — some carry-over effects from that prior period cannot be excluded.
Lumbar and hip BMD (the sites most predictive of fracture risk) did not reach statistical significance individually — the significant effect was on whole-body BMD, which is a less clinically actionable endpoint for fracture prevention.

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