Effects of Milk Protein and Vitamin D on Children's Growth and Health
- Conditions
- Cardiometabolic HealthMuscle FunctionAppetite RegulationBone Health
- Interventions
- Dietary Supplement: Milk Protein (high)Dietary Supplement: Vitamin DDietary Supplement: Milk Protein (medium)
- Registration Number
- NCT03956732
- Lead Sponsor
- University of Copenhagen
- Brief Summary
The purpose of D-pro is to investigate the combined and separate effects of milk protein and vitamin D on bone health, growth, muscle function, body composition and cardiometabolic health in 6-8-year-old children.
- Detailed Description
The D-pro study investigates the effects of high or medium intakes of milk protein, and vitamin D supplements or placebo, in healthy 6-8 year-old Danish children. The study is a 2×2-factorial randomized controlled trial with 4 study arms. The subjects will be randomly allocated to receive yoghurt products with either high or medium protein content (300g/day, 6 days/week) and to receive tablets with either vitamin D (20 μg/day) or placebo for 24 weeks. Measurements and biological sampling will be performed at baseline and at the end of the intervention.
The primary outcome will be bone mineral density (BMD). The investigators will also measure effects on children's muscle function, cardiometabolic health, body composition, growth and growth factors, nutrient status, immune defence and risk of acute respiratory tract infections, as well as appetite hormones. The investigators will also assess potential sex-specific effects and the potential modifying effect of genotype.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 200
Children must:
- Be 6-8 years of age at the start of the intervention
- Be healthy
- Have a frequent intake of milk and yoghurt products, corresponding to at least ¼ liter a day
- Like yoghurt and high protein yoghurt ("skyr")
- Be of white, Danish or European origin
Moreover:
- The family must not be planning a winter vacation south of a latitude of 50° North
- The child must speak and understand Danish in order to understand the study procedures
- At least one parent must read, speak and write Danish
- Known or suspected allergy or intolerance to milk or milk components
- Chronic illness or disease that may affect study outcomes
- Chronic intake of medicine that may affect study outcomes
- Use of vitamin D-containing supplements >3 days/week the 2 last months and use of any vitamin D-containing supplements the last 1 month before intervention start
- Concomitant participation in other studies involving dietary supplements or blood sampling
- Living in a household with another participating child
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- FACTORIAL
- Arm && Interventions
Group Intervention Description High protein yoghurt and vitamin D supplement Milk Protein (high) Subjects will receive high protein yoghurt and vitamin D tablets. High protein yoghurt and vitamin D supplement Vitamin D Subjects will receive high protein yoghurt and vitamin D tablets. High protein yoghurt and placebo supplement Milk Protein (high) Subjects will receive high protein yoghurt and placebo tablets of identical appearance and taste but without vitamin D. Medium protein yoghurt and vitamin D supplement Vitamin D Subjects will receive medium protein yoghurt and vitamin D tablets. Medium protein yoghurt and vitamin D supplement Milk Protein (medium) Subjects will receive medium protein yoghurt and vitamin D tablets. Medium protein yoghurt and placebo supplement Milk Protein (medium) Subjects will receive medium protein yoghurt and placebo tablets of identical appearance and taste but without vitamin D.
- Primary Outcome Measures
Name Time Method Bone Mineral Density (BMD) 24 weeks Measured by dual energy x-ray absorptiometry (DXA)
- Secondary Outcome Measures
Name Time Method Total cholesterol 24 weeks by fasting blood sample
Waist circumference 24 weeks Insulin-like Growth Factor 1 (IGF-1) 24 weeks by fasting blood sample
Fat free mass index 24 weeks by DXA
Bone Mineral Content (BMC) 24 weeks by DXA
Insulin-like growth factor-binding protein 3 (IGFBP-3) 24 weeks by fasting blood sample
Parathyroid hormone (PTH) 24 weeks by fasting blood sample
Blood pressure 24 weeks Height 24 weeks by stadiometer
Serum calcium 24 weeks by fasting blood sample
Osteocalcin 24 weeks by fasting blood sample
Bone-specific alkaline phosphatase 24 weeks by fasting blood sample
Maximal jumping length 24 weeks Measured by standing long jump
Muscle endurance 24 weeks Measured by 30 sec. sit-to-stand
Insulin 24 weeks by fasting blood sample
Fat mass index 24 weeks by DXA
Bone area 24 weeks by DXA
C-terminal telopeptide of type 1 collagen in serum (s-CTX) 24 weeks by fasting blood sample
Maximal jumping height 24 weeks Measured by squat jump with linear encoder
Glucose 24 weeks by fasting blood sample
High density lipoprotein cholesterol (HDL cholesterol) 24 weeks by fasting blood sample
Low density lipoprotein cholesterol (LDL cholesterol) 24 weeks by fasting blood sample
Maximal leg press strength 24 weeks Measured by isometric leg press
Hemoglobin A1c (HbA1c) 24 weeks by fasting blood sample
Maximal grip strength 24 weeks Measured by hand grip dynamometer
Triacylglycerol (TG) 24 weeks by fasting blood sample
Trial Locations
- Locations (1)
Department of Nutrition, Exercise and Sports, University of Copenhagen
🇩🇰Frederiksberg, Denmark