NCT02422784

Effects of Vitamin D Fortification on Vitamin D Metabolite Profiles and Status in Vitamin D Insufficient Individuals

A Double-Blind, Randomized, Control Study to Examine the Effects of Vitamin D Fortification on Vitamin D Metabolite Profiles and Status in Vitamin D Insufficient Individuals.

• Status: Withdrawn
• Phase: Phase 1
• Study type: Interventional
• Enrollment: 0 (actual)
• Sponsor: University of Manitoba · Academic / Other
• Sex: All
• Age: 19 Years – 50 Years
• Healthy volunteers: Accepted

Summary

This is a cross-sectional study designed to compare plasma/serum and urine vitamin D metabolite profiles of vitamin D sufficient and insufficient individuals. There are two phases of this study. Phase 1 - Consented study participants will attend a screening visit and provide a fasting blood and urine sample. Those individuals who are vitamin D insufficient based on serum 25(OH)D concentrations will be invited to participate in Phase II Phase II - is a double-blind, randomized, control study designed to examine vitamin D status in vitamin D insufficient individuals consuming a water-soluble form of vitamin D3. Eligible participants will be asked to consume one of three beverages: i) rooibos iced-tea (control); ii) rooibos iced-tea fortified with 1000 IU of water-soluble vitamin D3; or iii) rooibos iced-tea fortified with 1000 IU of water-soluble vitamin D3 and 360 mg calcium at 240 mL of iced-tea consumed daily for 6 weeks. Participants will attend 6 weekly visits following baseline and provide a fasting blood sample for assessment of serum 25(OH)D concentrations. Objectives: 1) To investigate plasma/serum and urine vitamin D metabolite profiles in vitamin D sufficient and insufficient individuals; and 2) To determine the effects of vitamin D3 fortification on serum 25-dihydroxy-vitamin D \[25(OH)D\] concentrations, markers of vitamin D and calcium metabolism, and vitamin D metabolite profile in plasma/serum and urine of vitamin D insufficient individuals.

Detailed description

Health individuals from the general public will be recruited into this cross-sectional study designed to compare plasma/serum and urine vitamin D metabolite profiles of those identified as vitamin D sufficient and insufficient individuals. There are two objectives: Objective 1: To investigate plasma/serum and urine vitamin D metabolite profiles in vitamin D sufficient and insufficient individuals; N=20 and will consist of 10 individuals identified as vitamin D insufficient and 10 individuals identified as vitamin D deficient individuals. Objective 2: To determine the effects of vitamin D3 fortification on serum 25-dihydroxy-vitamin D \[25(OH)D\] concentrations, markers of vitamin D and calcium metabolism, and vitamin D metabolite profile in plasma/serum and urine of vitamin D insufficient individuals. N=45. To achieve the objectives, the study will be conducted in two phases: Phase 1 - Healthy males or females, ≥19 and ≤50 years of age, will be recruited from the general public. Consented study participants will provide a fasting blood and urine sample for the purpose of determination of vitamin D status (insufficient vs. deficient) based on serum 25(OH)D concentrations. Forty-five (45) individuals identified as vitamin D insufficient (having a serum 25(OH)D concentration ≥30 and ≤75 nmol/L) will proceed to phase II. A N=20 (10 vitamin D insufficient and 10 vitamin D deficient) will also be identified to satisfy objective 1. Phase II - is a double-blind, randomized, control study designed to examine vitamin D status in vitamin D insufficient individuals consuming a water-soluble form of vitamin D3. Eligible participants will randomized to consume one of three beverages: i) rooibos iced-tea (control); ii) rooibos iced-tea fortified with 1000 IU of water-soluble vitamin D3; or iii) rooibos iced-tea fortified with 1000 IU of water-soluble vitamin D3 and 360 mg calcium at 240 mL of iced-tea consumed daily for 6 weeks. Both researchers and participants will be blinded to the beverage group assigned to each participant. Participants will then attend 6 weekly visits following the baseline visit to provide fasting blood samples for assessment of serum 25(OH)D concentrations. Analysis of intact-PTH, alkaline-phosphatase, calcium, phosphorus, CRP, TAP and vitamin D metabolite profile and a urine sample will also be obtained for assessment of N-telopeptide and vitamin D metabolite profile will also occur at Baseline and Week 6. Fasting blood samples collected at week 3 will be used for additional assessment of serum alkaline phosphatase, calcium and phosphorus. A 3-day Food Record will be provided at week 3. Vitamin D insufficient participants will be stratified according to their serum 25(OH)D concentrations (≥30 and ≤50, or \>50 and ≤75 nmol/L) after screening and prior to the beverage study to ensure that a range of lower and higher serum 25(OH)D concentrations are represented in each beverage group.

Conditions

• Vitamin D Deficiency

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Rooibos Iced-Tea (Control)	Participants will consume 240 mL of Rooibos iced-tea daily for 6 weeks. The iced-tea beverage will not contain any added sugar or artificial sweeteners. Beverages will be prepared fresh weekly and picked up by participants during their weekly study visits.
DIETARY_SUPPLEMENT	Rooibos Tea - Vitamin D3	Participants will consume 240 mL of Rooibos iced-tea fortified with 1000 IU of water soluable Vitamin D3 daily for 6 weeks. The iced-tea beverage will not contain any added sugar or artificial sweeteners. Beverages will be prepared fresh weekly and picked up by participants during their weekly study visits.
DIETARY_SUPPLEMENT	Rooibos Tea- Vitamin D3 & Calcium	Participants will consume 240 mL of Rooibos iced-tea fortified with 1000 IU of water soluable Vitamin D3 and 360 mg of Calicum daily for 6 weeks. The iced-tea beverage will not contain any added sugar or artificial sweeteners. Beverages will be prepared fresh weekly and picked up by participants during their weekly study visits.

Timeline

• Start date: 2016-07-01
• Primary completion: 2018-06-01
• Completion: 2018-06-01
• First posted: 2015-04-21
• Last updated: 2017-02-23

Locations

1 site across 1 country: Canada