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

Overview

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.

Full Title of Study: “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.”

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Randomized
    • Intervention Model: Parallel Assignment
    • Primary Purpose: Treatment
    • Masking: Double (Participant, Investigator)
  • Study Primary Completion Date: June 2018

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.

Interventions

  • 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.

Arms, Groups and Cohorts

  • Placebo Comparator: Control
    • Participants will be instructed to consume 240 mL of iced-tea daily for 6 weeks. The iced-tea beverages do not contain added sugar or artificial sweeteners. Beverages will be prepared fresh weekly and picked up by participants during their weekly study visits.
  • Active Comparator: Rooibos Tea – Vitamin D3
    • Participants will be instructed to consume 240 mL of iced-tea fortified with 1000 IU water-soluable vitamin D3 daily for 6 weeks. The iced-tea beverages do not contain added sugar or artificial sweeteners. Beverages will be prepared fresh weekly and picked up by participants during their weekly study visits.
  • Active Comparator: Rooibos Tea- Vitamin D3 & Calcium
    • Participants will be instructed to consume 240 mL of Rooibos iced-tea fortified with 1000 IU of water-soluable vitamin D3 and 360 mg of calcium daily for 6 weeks. The iced-tea beverages do not contain added sugar or artificial sweeteners. Beverages will be prepared fresh weekly and picked up by participants during their weekly study visits.

Clinical Trial Outcome Measures

Primary Measures

  • Plasma/Serum and Urine Vitamin D Metabolite Profiles of Vitamin D Sufficient and Insufficient Individuals
    • Time Frame: Screening Visit (Day 0) – Phase 1
    • To investigate plasma/serum and urine vitamin D metabolite profiles in vitamin D sufficient and insufficient individuals.
  • The Effects of Vitamin D Fortification on Serum 25(OH)D in Vitamin D Insufficient Individuals.
    • Time Frame: 6 Weeks (Phase II)
    • To determine the effects of 6 weeks of vitamin D3 fortification on serum 25-dihydroxy-vitamin D [25(OH)D] concentrations of vitamin D insufficient individuals.

Secondary Measures

  • The Effects of Vitamin D3 Fortification on markers of vitamin D of vitamin D insufficient individuals
    • Time Frame: 6 Weeks (Phase II)
    • To determine the effects of 6 weeks of vitamin D3 fortification on markers of vitamin D in plasma/serum and urine of vitamin D insufficient individuals.
  • The Effects of vitamin D3 Fortification on calcium metabolism of Vitamin D Insufficient Individuals.
    • Time Frame: 6 Weeks (Phase II)
    • To determine the effects of 6 weeks of vitamin D3 fortification on calcium metabolism in plasma/serum and urine of vitamin D insufficient individuals.
  • The Effects of Vitamin D3 Fortification on Vitamin D Metabolite Profile of Vitamin D Insufficient Individuals.
    • Time Frame: 6 Weeks (Phase II)
    • Determine the effects of vitamin D3 fortification on the vitamin D metabolite profile in plasma/serum and urine of vitamin D insufficient individuals.

Participating in This Clinical Trial

Inclusion Criteria

A. Inclusion Criteria for Objective 1 (Part One): 1. Adult volunteers, male or female, between 19 and 50 years of age; 2. Body mass index (BMI) ≥20 and ≤30 kg/m2 (normal to overweight); 3. Must be on a stable regime for the past three months, if taking vitamin and mineral/dietary/herbal supplements; and 4. Willing to provide informed consent. B. Inclusion Criteria for Objective 2 (Part Two): 1. Adult volunteers, male or female, between 19 and 50 years of age; 2. Body mass index (BMI) ≥20 and ≤30 kg/m2 (normal to overweight); 3. Must be on a stable regime for the past three months, if taking vitamin and mineral/dietary/herbal supplements; 4. Vitamin D insufficient (serum 25(OH)D concentrations ≥30 and ≤75 nmol/L); 5. Willing to comply with protocol requirements; and 6. Willing to provide informed consent. Exclusion Criteria:

1. Take a vitamin D or calcium supplement within the last three months before the start date of the study, or during the study; 2. History of vitamin D deficiency (serum 25(OH)D concentration <30 nmol/L); 3. History of hypocalcaemia; 4. Presence of a clinically diagnosed disease affecting the circulatory, respiratory, immune, skeletal, urinary, muscular, endocrine, digestive, nervous or reproductive system that requires medical treatment; 5. Taking any medication (with the exception of birth control); 6. Daily consumption of more than three servings of dairy products; 7. Undergone significant sun exposure one month before start date of the study; 8. Use or have used a tanning booth one month before start date of the study, or during the study; 9. Plan to travel to a sunny climate during the study; 10. Currently smoking or have smoked within the last six months before start date of the study, or during the study; 11. Have allergies to tea products; 12. Pregnant or lactating; and 13. Consume excessive alcohol (>10 drinks/week for women, >15 drinks/week for men).

Gender Eligibility: All

Minimum Age: 19 Years

Maximum Age: 50 Years

Are Healthy Volunteers Accepted: Accepts Healthy Volunteers

Investigator Details

  • Lead Sponsor
    • University of Manitoba
  • Collaborator
    • Canada Manitoba Agri-Food Research and Development Initiative
  • Provider of Information About this Clinical Study
    • Sponsor
  • Overall Official(s)
    • Carla Taylor, PhD, Principal Investigator, University of Manitoba

References

Calvo MS, Whiting SJ, Barton CN. Vitamin D fortification in the United States and Canada: current status and data needs. Am J Clin Nutr. 2004 Dec;80(6 Suppl):1710S-6S. doi: 10.1093/ajcn/80.6.1710S. Review.

Tangpricha V, Koutkia P, Rieke SM, Chen TC, Perez AA, Holick MF. Fortification of orange juice with vitamin D: a novel approach for enhancing vitamin D nutritional health. Am J Clin Nutr. 2003 Jun;77(6):1478-83.

Ding S, Schoenmakers I, Jones K, Koulman A, Prentice A, Volmer DA. Quantitative determination of vitamin D metabolites in plasma using UHPLC-MS/MS. Anal Bioanal Chem. 2010 Sep;398(2):779-89. doi: 10.1007/s00216-010-3993-0. Epub 2010 Jul 14.

Luque de Castro MD, Fernández-Romero JM, Ortiz-Boyer F, Quesada JM. Determination of vitamin D3 metabolites: state-of-the-art and trends. J Pharm Biomed Anal. 1999 Jun;20(1-2):1-17. Review.

Stalmach A, Mullen W, Pecorari M, Serafini M, Crozier A. Bioavailability of C-linked dihydrochalcone and flavanone glucosides in humans following ingestion of unfermented and fermented rooibos teas. J Agric Food Chem. 2009 Aug 12;57(15):7104-11. doi: 10.1021/jf9011642.

Clinical trials entries are delivered from the US National Institutes of Health and are not reviewed separately by this site. Please see the identifier information above for retrieving further details from the government database.

At TrialBulletin.com, we keep tabs on over 200,000 clinical trials in the US and abroad, using medical data supplied directly by the US National Institutes of Health. Please see the About and Contact page for details.