Casein peptides and mineral absorption in animals and people
What it found
Casein phosphopeptides improved mineral solubility and absorption in short lab and animal experiments, but long-term animal studies found little lasting effect on bone.
Human studies were rare and short.
What they found
Studies in people
Human studies
In single-meal experiments, casein phosphopeptides improved calcium and zinc absorption from rice-based cereal in 22 young adults, but not from whole-grain cereal. In osteoporotic women with low absorption, calcium absorption improved in a single meal.
Animal and lab studies
Mineral solubility in lab tests
In lab tests, casein phosphopeptides bound calcium and kept it soluble, preventing calcium phosphate from precipitating. This raised the amount of soluble calcium.
Calcium absorption in animals
In rats and chicks, casein phosphopeptides increased calcium disappearance from intestinal loops and calcium incorporation into bone. The effect was dose-dependent and not vitamin D-dependent.
Long-term bone effects in minipigs
In minipigs fed casein or whey protein for 12 weeks, changes in calcium metabolism were small and only seen at low dietary calcium or when vitamin D was insufficient. There was no lasting effect on bone mineralisation.
Other minerals
In young iron-deficient rats, iron bound to casein phosphopeptides improved some iron status measures and helped cure iron deficiency. Zinc absorption was improved in rat pups when calcium-containing casein phosphopeptides were given with phytate.
Tooth effects
Casein phosphopeptides stabilised calcium phosphate and helped remineralise tooth enamel in lab models. They also reduced adhesion of cavity-causing microbes.
What the authors conclude
- They conclude that long-term studies in humans are needed to confirm any beneficial effects on bone health.
- They advise that bone density or other measures of bone quality should be monitored if claims about bone health are made.
How it was done
The authors wanted to review whether casein phosphopeptides, which had been reported to improve calcium balance in rachitic newborns over 50 years ago, could benefit bone health for some groups of the population.
They reviewed experiments on casein and casein phosphopeptides, including lab tests, single-meal studies, short-term rat studies, long-term minipig studies, and a few short human studies.
What it can’t tell you
- Most of the evidence comes from lab tests and short-term animal studies, so it cannot show what happens in people over time.
- The long-term animal studies found little lasting effect on bone, so the short-term improvements may not translate to better bone health.
- Human studies were rare and mostly single meals, so they cannot show whether casein phosphopeptides affect bone density or fracture risk.
Who paid
- Authors work at
- Federal Dairy Research Center, Germany
The paper
- Title
- Effects of bioactive substances in milk on mineral and trace element metabolism with special reference to casein phosphopeptides
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Cite
- Scholz-Ahrens KE, Schrezenmeir J (2000). Effects of bioactive substances in milk on mineral and trace element metabolism with special reference to casein phosphopeptides. The British journal of nutrition. doi:10.1017/s0007114500002373Free full textPubMed 11242459DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error