Skip to main content
OpenTrials
Recruiting

NCT Number: NCT07436260

Effect of the Consumption of Milk With Beta-casein A2A2, Milk With Beta-casein A1A2 and a Plant-based Drink on Metabolic Health in Adults: IMPA-CT Study

The purpose of this study was to identify and compare the effects of daily consumption of A2 milk, conventional milk, and an oat drink on bone health, cardiometabolic health, and immune system function in adults. Although cow's milk plays an important role in human nutrition, its proteins-particularly β-caseins-exhibit significant genetic diversity. Conventional milk typically contains a mix of A1 and A2 β-casein variants, whereas A2 milk contains exclusively the A2/A2 variant. The key difference between the two lies in a single amino acid at position 67: variant A1 contains histidine, which allows digestive enzymes to release the opioid peptide β-casomorphin-7 (BCM-7), while variant A2 contains proline, which prevents the release of this peptide. Consequently, the study is trying to answer the question of whether 12 weeks of consuming 500 ml of A2 milk daily-thereby eliminating dietary exposure to BCM-7-results in different outcomes for bone health (the primary measure), as well as for cardiometabolic health and immune function, when compared to consuming conventional milk or a plant-based oat drink in healthy adults aged 30-60.

Recruiting

Interested in participating?

Request Info

Key information

Conditions

Healthy Participants

Age range

30 year–60 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Warsaw Univeristy of Life Science

Warsaw, Masovian Voivodeship, 02-776, Poland

Location status: Recruiting

Location contact

Jadwiga Hamulka Prof. dr hab., Prof. dr hab.

CONTACT

[email protected]

048 22 59 37 112

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • aged 30 to 60 years,
  • body mass index >18.5 or <30 kg/m2,
  • no diagnosed chronic disease, i.e. diabetes, cancer, kidney disease,
  • not taking medications/dietary supplements that may affect carbohydrate and/or lipid metabolism.

Exclusion criteria

  • pregnancy or lactation in women,
  • implanted medical materials such as: pacemaker, defibrillator, stent, metal suture in the heart or blood vessel, and implants,
  • previous radiotherapy and/or chemotherapy,
  • significantly modified diet (e.g., ketogenic, vegetarian, or ovo-vegetarian) and health condition requiring a specialist diet,
  • unable to give informed consent,
  • unable or unwilling to comply with the study procedures,
  • have medical history of gastrointestinal surgery or disorders (inflammatory bowel disease, ulcerative colitis, coeliac disease, Crohn's disease), cardiorespiratory problems, uncontrolled diabetes mellitus, bleeding disorders.

Non-exclusion criteria:

  • hypertension, or depression that are well-controlled with medical intervention.

Treatment and study plan

Consumption 500 ml of A1 milk.

Other

The intervention study consisted of the consumption 500 ml of an appropriate product: A1 milk - daily for a 12 weeks.

Consumption 500 ml of A2 milk

Other

The intervention study consisted of the consumption 500 ml of an appropriate product: A2 milk - daily for a 12 weeks.

Consumption 500 ml of oat drink.

Other

The intervention study consisted of the consumption 500 ml of an appropriate product: oat drink - daily for a 12 weeks.

Primary outcomes

  1. Change from Baseline in Bone Mineral Density (BMD)

    Time frame: Baseline, and after 4, 8 and 12 weeks of intervention.

    Assessment of changes in bone mineral density (BMD) using Dual-energy X-ray Absorptiometry (DEXA).

Secondary outcomes

  1. Change from Baseline in Plasma Procollagen Type 1 N-terminal Propeptide (P1NP) Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in P1NP as a biochemical marker of bone formation.

  2. Change from Baseline in Bone Alkaline Phosphatase (BALP) Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in BALP as a biochemical marker of bone formation.

  3. Change from Baseline in Plasma C-terminal Telopeptide of Type 1 Collagen (CTX-1) Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in plasma CTX-1 as a biochemical marker of bone resorption.

  4. Change from Baseline in Urinary Calcium Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in urinary calcium levels as a marker of bone resorption.

  5. Change from Baseline in Urinary Deoxypyridinoline Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in urinary deoxypyridinoline levels as a marker of bone resorption.

  6. Change from Baseline in Plasma Calcium Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in plasma calcium levels as a marker of bone homeostasis.

  7. Change from Baseline in 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in 1,25(OH)2D3 levels as a marker of bone homeostasis.

  8. Change from Baseline in Body Mass Index (BMI)

    Time frame: Baseline, and after 4, 8 and 12 weeks of intervention.

    Weight and height will be combined to report BMI in kg/m^2.

  9. Change from Baseline in Waist-Hip Ratio (WHR)

    Time frame: Baseline, and after 4, 8 and 12 weeks of intervention.

    Assessment of fat distribution calculated as waist measurement divided by hip measurement (unitless ratio).

  10. Change from Baseline in Waist-to-Height Ratio (WHtR)

    Time frame: Baseline, and after 4, 8 and 12 weeks of intervention.

    Assessment of fat distribution calculated as waist measurement divided by height (unitless ratio).

  11. Change from Baseline in Ankle-Brachial Index (ABI)

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of cardiovascular health using blood pressure measurements to calculate the Ankle-Brachial Index (ABI).

  12. Change from Baseline in Body Fat Mass

    Time frame: Baseline, and after 4, 8 and 12 weeks of intervention.

    Assessment of changes in body fat mass, assessed by BIA and DEXA. Results will be reported in kilograms (kg).

  13. Change from Baseline in Body Fat Percentage

    Time frame: Baseline, and after 4, 8 and 12 weeks of intervention.

    Assessment of changes in total body fat content, assessed by BIA and DEXA. Results will be reported as a percentage (%).

  14. Change from Baseline in Visceral Fat Area

    Time frame: Baseline, and after 4, 8 and 12 weeks of intervention.

    Assessment of changes in visceral fat assessed by BIA and DEXA. Results will be reported in square centimeters (cm^2).

  15. Change from Baseline in Cholesterol Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in total cholesterol, High-Density Lipoprotein (HDL) and Low-Density Lipoprotein (LDL) Cholesterol Concentration as part of the lipid profile.

  16. Change from Baseline in Triglycerides Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in triglycerides as part of the lipid profile.

  17. Change from Baseline in Fasting Glucose Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in fasting blood glucose levels.

  18. Change from Baseline in Fasting Insulin Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in fasting insulin levels.

  19. Change from Baseline in Insulin-like Growth Factor-1 (IGF-1) Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in IGF-1 levels.

  20. Change from Baseline in IGF-Binding Protein-3 (IGFBP-3) Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in IGFBP-3 levels.

  21. Change from Baseline in High-Sensitivity C-Reactive Protein (hsCRP) Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in hsCRP as a marker of systemic inflammation.

  22. Change from Baseline in Uric Acid Concentration at 12 Weeks

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in uric acid levels.

  23. Change from Baseline in Creatinine Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in creatinine levels.

  24. Baseline, and after 12 weeks of intervention.

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in plasma levels of Immunoglobulin A (IgA) as an indicator of immune system functioning.

  25. Change from Baseline in Immunoglobulin G (IgG) Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in plasma levels of Immunoglobulin G (IgG) as an indicator of immune system functioning.

  26. Change from Baseline in Allergen-specific Immunoglobulin E (sIgE) Concentration

    Time frame: Baseline, and after 12 weeks of intervention.

    Assessment of changes in allergen-specific Immunoglobulin E (sIgE) as a marker for potential casein allergy.

Study contacts

Contact information is provided by the study sponsor or research team.

Jadwiga Hamulka Prof. dr hab., Prof. dr hab.

CONTACT

[email protected]

(48)0225937112

Sponsors and collaborators

Lead sponsor

Dawid Madej

Other

Registry information

Acronym: IMPA-CT

Important dates

Study start
2025
Primary completion
2026
Study completion
2026
First posted
Feb 27, 2026
Registry last updated
Feb 27, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.