Dietary vitamin D intake and status Nutritional, Metabolic, Endocrine Dietary intake
Conditions
Interventions
Oral daily supplementation with vitamin D3 of the following doses:
1. Placebo (no treatment)
2. 5 mcg
3. 10 mcg
4. 15 mcg
Supplementation is provided for six months from October to March. There is n
Sponsors
Food Standards Agency (UK)
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Consenting adult men and women 2. Aged 20 - 85 years 3. In general good health
Exclusion criteria
Exclusion criteria: 1. Severe medical illness 2. Hypercalcaemia 3. Known intestinal malabsorption syndrome 4. Excessive alcohol use 5. Those who took medications known to interfere with vitamin D metabolism 6. Pregnancy or planning to become pregnant during the six months of the intervention 7. Those taking high dose vitamin D-containing supplements for three months before initiation of study 8. Those who over the six-month course of intervention are planning a winter vacation to a location at which either the altitude or the latitude would be predicted to result in significant cutaneous vitamin D synthesis from solar radiation (e.g., a mountain ski resort or a winter sun coastal resort)
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| 1. Serum 25 hydroxyvitamin D concentrations 2. Serum parathyroid hormone concentrations 3. Serum calcium concentrations 4. Dietary calcium and vitamin D intakes (from four-day food diary and food frequency questionnaire) | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. Bone mineral density (from dual energy x-ray absorptiometry [DXA] scan of spine, hip and whole body) 2. Body composition measurements 3. Immune markers 4. Bone turnover markers | — |
Countries
Ireland
Outcome results
None listed