Four randomised trials have given collagen to women and measured their bones. Two found a small benefit over a year; both used 5 g a day of the same branded collagen peptide, and both record support from the company that makes or sells it. One trial of a generic hydrolysate found nothing on bone markers. One used a calcium-collagen compound that is a different product. None counted fractures, which is what bone density is measured to predict.
That is the whole controlled record found for this page, and it is all in postmenopausal women. Bone density questions about men, younger women or athletes have no collagen trial behind them. The muscle, joint and tendon trials are on other pages; this one is bone only.
The census
PubMed was searched on 27 October 2026 for randomised trials of collagen peptides or collagen hydrolysate with women, female, premenopausal or postmenopausal in the title. It returned 17 records. Four are trials that gave collagen and measured bone; one more is a companion paper of one of them. A broader search for collagen peptides, bone mineral density and randomised trials in any population added no further bone trial.
| Trial | Women | Collagen given | Comparison | Length | Bone result |
|---|---|---|---|---|---|
| König 2018 | 131 postmenopausal, low BMD (102 completed) | 5 g/day FORTIBONE peptide | Placebo (maltodextrin) | 12 months | Spine and femoral-neck BMD up vs placebo |
| Lampropoulou-Adamidou 2022 | 51 postmenopausal, osteopenia | 5 g/day peptide + 500 mg calcium + 400 IU D3 | Calcium + D3 | 12 months | Tibial trabecular density up; spine aBMD higher |
| Elam 2015 | 39 postmenopausal, osteopenia | 5 g/day calcium-collagen chelate (500 mg calcium, 200 IU D) | Calcium + D | 12 months | Less whole-body BMD loss |
| Cúneo 2010 | 71 postmenopausal, osteopenia | 10 g/day hydrolysate | Placebo | 24 weeks | No difference in bone markers; BMD not measured |
König 2018: the trial the claims rest on
The largest trial enrolled 131 women (mean age 64, spine T-score −2.4, so many in the osteoporosis range) and gave 5 g a day of a specific collagen peptide or a maltodextrin placebo for 12 months, double-blind. 102 finished; all 131 were analysed.
| König 2018, T-score change over 12 months | Collagen (n = 66) | Placebo (n = 65) |
|---|---|---|
| Spine | +0.10 | −0.03 |
| Femoral neck | +0.09 | −0.01 |
Both differences were statistically significant. A bone-formation marker (P1NP) rose on collagen; a breakdown marker (CTX) rose on placebo. The peptide was FORTIBONE, made by GELITA AG, and the paper's acknowledgments state that "part of the study was financially supported by GELITA AG", with planning and analysis done by the investigators. One author is from the Collagen Research Institute in Kiel.
A T-score change of 0.1 is about a tenth of a standard deviation of young-adult bone density. It moved the average participant from losing density to holding or gaining slightly; it did not move anyone out of the osteoporosis range on average.
The four-year follow-up (Zdzieblik 2021) is often quoted with the trial. It is an open-label observation of 31 women who kept taking the same peptide, with no control group; the authors report further density gains and recorded fractures. Without a comparison group it cannot separate the peptide from time, other treatment or who chose to continue. One author declares lecture support from GELITA and co-inventorship of collagen-peptide patents.
The other three trials
Lampropoulou-Adamidou 2022 (Athens). 51 women with osteopenia took either a sachet of 5 g collagen peptides with 500 mg calcium and 400 IU vitamin D3, or a chewable tablet with the same calcium and vitamin D, for a year. Measured by peripheral CT at the tibia, the collagen group's trabecular density rose 2.5% and its trabecular mineral content 5.2%, more than the other group; spine density by DXA was higher and turnover markers fell. Two things to know: the collagen in the sachet (Colabone) is again Fortibone, supplied by Vivapharm SA, which supported the study; and the two groups received different forms of calcium — lactate in the sachet, carbonate in the tablet — so the comparison is not collagen alone.
Elam 2015 (Florida State). 39 women with osteopenia took 5 g of a calcium-collagen chelate (with 500 mg calcium and 200 IU vitamin D) or calcium and vitamin D alone for 12 months. Whole-body density fell 1.3% on the chelate against 3.8% on control among completers. A chelate is a bound calcium-collagen compound, not a collagen peptide powder, so the result describes that product.
Cúneo 2010 (Brazil). 71 women with osteopenia took 10 g a day of collagen hydrolysate or placebo for 24 weeks. Bone-turnover markers moved the same way in both groups, and "no significant effect" was the authors' conclusion. Bone density was not scanned. Most participants had low calcium intake and excess weight, which the authors note.
What the 2025 meta-analysis adds
Sun and colleagues (2025, Frontiers in Nutrition) pooled randomised trials of collagen peptides alone or with calcium and vitamin D. They report higher femoral-neck and spine density on collagen, better bone-turnover markers and muscle performance, and larger effects when collagen was combined with calcium and vitamin D. Their abstract also reports I² = 80.1% for the density results — the trials disagreed with each other more than chance explains — and, although fracture probability is named among its aims, it reports no fracture result. The pooled finding rests largely on the trials above.
Who paid
| Trial | Collagen product | Industry tie stated in the paper |
|---|---|---|
| König 2018 | FORTIBONE (GELITA AG) | Part-funded by GELITA; an author from the Collagen Research Institute |
| Lampropoulou-Adamidou 2022 | Colabone sachets containing Fortibone | Supported and supplied by Vivapharm SA |
| Elam 2015 | Calcium-collagen chelate | Not established from the abstract |
| Cúneo 2010 | Generic hydrolysate | None stated in the abstract |
The two trials with positive density results used the same ingredient with commercial support. That does not make them wrong; it means the bone evidence for collagen is, in practice, the evidence for one product, and no independent replication of it was found. The same pattern — supplier involvement in most collagen trials — runs through the male trials too.
What is not established
- Fractures. No collagen trial has counted them, and density gains of this size are not proof of fewer fractures.
- Men. No collagen bone trial in men was found.
- Generic collagen. The one generic hydrolysate trial found no effect on markers and did not scan bone; whether ordinary collagen powders do what the branded peptide did is untested.
- Collagen against osteoporosis medicine. No head-to-head trial exists. Anyone with osteopenia or osteoporosis, or on bone medicine, should take this to the clinician managing it; no trial here supports changing treatment.
- Training. None of the bone trials paired collagen with a resistance-training programme; creatine has a 12-month trial that did, in postmenopausal women, set out on creatine and menopause.
What collagen does for joints and tendons is on collagen for joints; the women-specific summary across muscle, bone and tendon is on collagen for women; the amounts used across all collagen trials are on how much collagen per day; and the overview is on collagen peptides benefits.
Sources and dates
- PubMed searches via NCBI E-utilities, 2026-10-27: randomised trials of collagen peptides/hydrolysate with women, female, premenopausal or postmenopausal in the title (17 records); collagen peptides, bone mineral density and randomised trial (4 records).
- König D et al. (2018), Specific collagen peptides improve bone mineral density and bone markers in postmenopausal women, Nutrients 10(1):97, PMID 29337906, full text PMC5793325 (product and funding, read 2026-10-27).
- Zdzieblik D, Oesser S, König D (2021), long-term observation in postmenopausal women, J Bone Metab 28(3):207–13, PMID 34520654.
- Lampropoulou-Adamidou K et al. (2022), J Clin Densitom 25(3):357–72, PMID 34980546; companion bone-turnover paper (2020), PMID 32131366 (product and support statement), NCT03999775.
- Elam ML et al. (2015), calcium-collagen chelate in postmenopausal women with osteopenia, J Med Food 18(3):324–31, PMID 25314004.
- Cúneo F et al. (2010), collagen hydrolysates and bone metabolism in postmenopausal women, Maturitas 65(3):253–7, PMID 19892499.
- Sun C et al. (2025), Efficacy of collagen peptide supplementation on bone and muscle health: a meta-analysis, Front Nutr 12:1646090, PMID 41049371.