Effect of Vitamin D Supplementation on Muscular Strength, Musculoskeletal Pain and Headache
Condition: Vitamin Deficiency
MeSH terms: Musculoskeletal Pain; Avitaminosis; Headache
Study type: Interventional
Phase: Phase 4

Summary: 
      The primary aim of the present trial is to study the effect of daily vitamin D
      supplementation on muscular power and force among non-western immigrants living in Oslo,
      Norway, and secondarily to study the effect of musculoskeletal pain and headache.

      The investigators have also prespecified a number of additional research questions about
      anemia, metabolism and bone turnover, inflammation, diabetes, lipids, itching and kidney
      function, which because of multiple comparisons should be interpreted with caution unless the
      statistical evidence for an effect is very strong.
    

Detailed description: 
      Vitamin D deficiency is a widespread public health problem among immigrants from non-Western
      countries in Norway. As a background for preventive strategies it is important to have best
      possible knowledge about health consequences of poor vitamin D status, and in this respect
      much is lacking.

      The investigators will aim to study the effect of vitamin D supplementation on muscular
      strength , musculoskeletal pain and headache among non-western immigrants in Norway with
      background from Middle East, Africa and South Asia. In addition the intervention gives us the
      opportunity to study the effect of vitamin D on indicators of other important health issues
      including anemia, diabetes , lipids, inflammation, metabolism and bone health. The study will
      also contribute with insight on how to achieve a high compliance. This is of interest in a
      broader context as poor compliance has been experienced as a problem in primary health care
      among immigrants with poor vitamin D status.

      The study is a randomized, double blinded, placebo-controlled trial which compares two doses
      of vitamin D supplements, 400 IU and 1000 IU, with placebo and the tablets will be taken
      daily in a period of 4 months. Three muscle strength tests will be used, and they will be
      performed before and after the intervention: Counter movement jumps, Chair rising and
      Handgrip. Level and location of musculoskeletal pain and headache will be recorded at
      baseline and at end of the study.

      A blood sample will be collected from the study subjects at baseline and after 4 months. The
      level of vitamin D and markers of anemia, metabolism and bone turnover, inflammation,
      diabetes, lipids and kidney function will be measured.
    

Intervention name(s): cholecalciferol; cholecalciferol; Placebo
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): Vitamin D3 tablet 400 IU. Once daily by mouth for 4 months; Vitamin D3 tablet 1000 IU. Once daily by mouth for 4 months; Microcrystalline cellulose tablet p.o.daily. (Same color, shape and size as vitamin D tablet)
Other intervention name(s): NN007; NN008; NN009
Intervention MeSH terms: Cholecalciferol; Vitamin D
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Prevention