Dietary Requirement for Vitamin D in Adolescents Aged 14-18 Years

Serum 25-hydroxyvitamin D Concentrations (25OHD) Clinical Trial

Official title:

A Dose-response, Double-blind Randomised Placebo-controlled Trial to Estimate the Dietary Requirement for Vitamin D in Caucasian Male and Female Adolescents Aged 14-18 Years (The ODIN Study)

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02150122
• Other study ID #: ODIN/1213
• Status: Completed
• Phase: N/A
• First received: May 23, 2014
• Last updated: March 1, 2016
• Start date: October 2014
• Est. completion date: March 2015

Study information

• Verified date: March 2016
• Source: University of Surrey
• Contact: n/a
• Is FDA regulated: No
• Health authority: UK: National Health Service (NHS)
• Study type: Interventional

Clinical Trial Summary

It is known that low vitamin D status is a very common problem in the UK. It is also known that a lack of vitamin D availability has potentially serious health implications, especially with respect to bone and muscle function. Much research has recently taken place to establish the vitamin D requirements of key population groups (i.e. pregnant women, the elderly, ethnic minorities). However few data are available describing the vitamin D requirements for male and female adolescents. The period of adolescence is a key stage of growth and development - poor nutrition during this time can have detrimental health consequences for a lifetime.

No intervention studies have comprehensively investigated the vitamin D requirements of adolescents. The proposed ODIN Study will enable a better understanding of how adolescents respond to vitamin D supplementation and the most effective daily amount that will raise and maintain vitamin D status in adolescents during the winter-time. In addition, investigations into the mechanisms of action with respect to any differences observed across the doses of vitamin D and between the genders of the participants will also provide key information. Mechanisms of action will focus on genetic differences as well as differences in vitamin D metabolising enzymes.

The results obtained from this significant study will not only inform the European Food Standards Agency (EFSA) with respect to their imminent deliberations regarding vitamin D recommendations. The ODIN Study will also inform the UK Department of Health's Scientific Advisory Committee on Nutrition (SACN), the wider scientific community and be a critical resource for key stakeholders (i.e. food industry, government health agencies) to collaborate in determining future public health strategies, thus potentially positively impacting on the health of the population for years to come.

The investigators propose that the daily supplementation of 10µg/day (400 IU) and 20µg/day (800 IU) of vitamin D3 for five months will meet the vitamin D requirements of males and females aged 14-18 year and will be sufficient to maintain winter-time 25OHD levels above a range of thresholds between 30 and 50nmol/l.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 120
• Est. completion date: March 2015
• Est. primary completion date: March 2015
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 14 Years to 18 Years

Eligibility

Inclusion Criteria:

• Male or female

• Aged between 14 and 18 years

• Caucasian ethnicity

• In good health

• Written informed consent from the adolescent (and parent if required)

Exclusion Criteria:

• Currently receiving treatment for medical conditions likely to affect vitamin D metabolism

• Hypercalcaemia (>2.5mmol/l)

• Regular use of sun-beds

• Having a sun holiday one month prior to commencing the trial or plans for a sun holiday within the study period.

• Use of vitamin supplements containing vitamin D - if the prospective participant agrees to stop vitamin D supplementation to join the study, a wash-out period of 8 weeks prior to commencing the trial would be acceptable.

• Excessive consumption of alcohol (>14 units per week for females, >21 units per week for males)

• Smoking >10 cigarettes per day

• Those following a weight-reducing diet or under dietary restriction (except vegetarianism)

• Known intolerance/allergy to the constituent ingredients of the daily supplement

• Clinically significant haematological abnormalities other than mild anaemia (Hb<12.0g/dl)

• Active malignancy

• Pregnant or planning a pregnancy during the study period.

• Breast-feeding mothers

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Serum 25-hydroxyvitamin D Concentrations (25OHD)

Intervention

Dietary Supplement:
• Vitamin D3

Locations

Country	Name	City	State
United Kingdom	University of Surrey	Guildford	Surrey

Sponsors (1)

Lead Sponsor	Collaborator
University of Surrey

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Identification of genetic polymorphisms for vitamin D	To investigate the mechanisms (genetic/enzymatic) underlying the differences observed in the preceding objective via genotyping the participants for polymorphisms related to vitamin D metabolism. Secondary analyses will include evaluation of variations in the response to supplementation by single SNP variations and by the genetic vitamin D risk score. To determine, through transcriptomic (global mRNA) analysis of leukocyte samples, genome-wide differences in gene expression, in the adolescents in response to the vitamin D3 supplementation.	Baseline and after 5 months of supplementation	No
Other	Family links in vitamin D levels and bone health	To determine the bone mineral density and vitamin D levels (in addition to the assessment of related blood markers and lifestyle factors) of the mothers of the adolescent participants, in order to establish possible familial links in the factors that affect vitamin D status and bone health.	Baseline	No
Primary	Serum 25-hydroxyvitamin D concentrations	To investigate the vitamin D intakes needed to maintain serum 25-hydroxyvitamin D (25OHD) concentrations above the deficiency and insufficiency cut off thresholds (30nmol/l and 50nmol/l respectively) in male and female adolescents during the winter time.	Baseline and after 5 months of supplementation	No