Study · Molecules (Basel, Switzerland) · 2020Conflicts declared

Collagen peptide and calcium citrate in tail-suspended rats

What it found

In rats with simulated microgravity, collagen peptide alone or with calcium citrate did not stop bone loss, but it partly protected bone structure.

The study was in animals.

What they found

Animal and lab studies

Bone density

Rats with simulated microgravity had 17.82% lower femoral bone mineral density than normal rats. Neither collagen peptide nor the combination improved this density.

Bone strength

The maximum force to break the femur dropped by 31.65% in simulated microgravity groups. Collagen peptide and the combination gave only a slight increase, not a significant one.

Bone structure

Collagen peptide and the combination increased trabecular number by 67.52% and 79.17%, and decreased trabecular separation by 34.52% and 41.94%, compared with untreated simulated microgravity rats.

Bone formation marker

The combination raised serum osteocalcin levels to be similar to normal rats. Calcium citrate alone did not.

Bone resorption marker

Serum beta-CTX levels were slightly reduced in tail-suspended rats, and TRACP-5b levels were not altered.

What the authors conclude

“Bovine CP, alone or in combination with CC, did not inhibit bone loss in a tail-suspended rat model of microgravity.”
Liu J, Wang J, Guo Y, 2020

Also in their conclusions

  • They conclude that bovine collagen peptide, alone or with calcium citrate, did not inhibit bone loss in a tail-suspended rat model of microgravity.
  • They state that collagen peptide or the combination partially ameliorated the microgravity-induced deterioration of bone microarchitecture.
  • They suggest this may represent an adjunct dietary strategy to reduce the risk of fracture in astronauts and highly sedentary populations.

How it was done

The authors wanted to see if collagen peptide, alone or with calcium citrate, could help prevent bone loss caused by microgravity, since this had not been tested in a tail-suspension rat model.

Forty male Sprague-Dawley rats were divided into five groups. Three groups with simulated microgravity received daily doses of collagen peptide (750 mg/kg), calcium citrate (75 mg/kg), or both for 28 days. Bone density, strength, structure, and blood markers were measured.

What it can’t tell you

  • These are animal studies. They can't show what happens in people.
  • The study lasted only 28 days, which may be too short to see full effects on bone density.
  • The authors note that no dose-response effect was seen and blood was not sampled continuously.

The paper

Title
Effect of Collagen Peptide, Alone and in Combination with Calcium Citrate, on Bone Loss in Tail-Suspended Rats
Type
Study
Evidence
Animals and lab studies
Summarised from
Full text
Cite
Liu J, Wang J, Guo Y (2020). Effect of Collagen Peptide, Alone and in Combination with Calcium Citrate, on Bone Loss in Tail-Suspended Rats. Molecules (Basel, Switzerland). doi:10.3390/molecules25040782Free full textPubMed 32059436DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error