Condition category
Nutritional, Metabolic, Endocrine
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Background and study aims:
Vitamin D is an unusual vitamin because for most people sunlight, not food, is the major source of the vitamin. It is well known that vitamin D is important for bones but recent research has linked vitamin D with other health outcomes, including heart health. This could have implications in the UK, because between the months of October and April, there is a lower strength of the type of sunlight we need to make vitamin D in the skin.
This study investigated whether giving daily vitamin D supplements could help reduce heart disease risk in postmenopausal women over one year.

Who can participate?
Healthy postmenopausal women aged between 60-70 years living in the Aberdeen area.

What does the study involve?
Participants were randomly allocated to receive either high or low dose vitamin D or placebo (dummy vitamin). Participants were asked to take one capsule every day with breakfast for 12 months. At each visit, study investigators collected a small blood sample to assess vitamin D status and a range of factors related to heart health. Participants were also asked to complete questionnaires on physical activity and habitual diet. Questions relating to general health, chronic pain, sun exposure and holidays abroad were also asked. After each visit, participants were asked to wear a small polysulphone film badge on the lapel on their outside coat or jacket for one week to measure sunlight exposure. At the beginning and end of the study, the participants’ bone mineral density and body composition were measured.

What are the possible benefits and risks of participating?
There are no direct benefits other than the information that participants will receive from their GP about their bone health after the bone scan. There are minor risks associated with blood collection which include excessive bleeding, fainting or feeling light headed, haematoma (blood collecting under the skin), and infection (a slight risk any time the skin is broken). There is a minor radiation exposure from the bone scan (similar to background radiation in Aberdeen).

Where is the study run from?
University of Aberdeen, UK

When is the study starting and how long is it expected to run for?
The study started in September 2008 and ended in 2010

Who is funding the study?
Department of Health, UK
National Osteoporosis Society, UK

Who is the main contact?
Dr Helen M Macdonald

Trial website

Contact information



Primary contact

Dr Helen Macdonald


Contact details

Osteoporosis Research Unit
Health Sciences Building
University of Aberdeen
AB25 2ZD
United Kingdom
+44 (0)1224 559001

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Effect of one year vitamin D intervention on risk of cardiovascular disease: a randomised controlled trial at 57°N



Study hypothesis

1. Does supplementing the diet with high or low doses of oral vitamin D3 (25 µg [dietary recommendations in the United States of America] or 10 µg [United Kingdom reference nutrient intake for over 65 year olds, or individuals at risk of vitamin D deficiency] daily respectively) reduce cardiovascular disease (CVD) risk markers and insulin sensitivity?
2. Does supplementing the diet with high or low doses of oral vitamin D3 (25 µg or 10 µg daily respectively) raise vitamin D status equally in overweight and lean individuals, and does adipose tissue distribution influence vitamin D status?

Ethics approval

Approval has been sought from the National Health Service Ethics Committee (NHS REC): Grampian Local Research Ethics Committee. Submitted on 22nd April 2008 and a decision will be made on the 8th May 2008 (ref: 08/S0802/73).

Study design

Randomised double blind placebo controlled trial - single centre

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type

Quality of life

Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Vitamin D status, CVD risk, insulin sensitivity


This is a randomised double blind placebo controlled trial with supplementation starting in January 2009, aiming to assess whether dietary supplementation with oral vitamin D3 (10 µg or 25 µg) daily for 12 months reduces cardiovascular risk and insulin sensitivity. This could influence policy making decisions regarding dietary guidelines and in particular help set reference nutrient intakes using non-bone health outcomes in the over 60s. As there is concern that for any given intake of dietary vitamin D the circulating 25(OH)D does not increase as expected in overweight individuals, we will determine whether distribution of adipose tissue influences the effectiveness of the intervention, which will help to identify 'at risk' individuals.

Study visits will be held at two monthly intervals for 12 months (eight visits in total). Participants will be randomised to receive placebo, 10 µg or 25 µg oral vitamin D3. We will use minimisation criteria for vitamin D receptor (VDR) genotype, apolipoprotein E (ApoE) genotype (which is known in our study cohort), overweight (greater than or less than 25 kg/m^2) and smoking, so that the groups will be equally matched.

Intervention type



Not Specified

Drug names

Oral vitamin D3 supplementation

Primary outcome measure

All primary and secondary outcomes will be measured at each study visit, i.e. at baseline, 2-, 4-, 6-, 8-, 10- and 12-month visits. Adipose tissue distribution will be measured at pre- and post-supplementation visits only.

1. Blood samples will be analysed for total cholesterol, high density lipoprotein (HDL)-cholesterol, low density lipoprotein (LDL)-cholesterol, triglycerides, apolipoprotein A1, apolipoprotein B100, fasted serum glucose, non-esterified fatty acids, insulin, glucose, intercellular adhesion molecule-1 (ICAM-1), interleukin-6 (IL-6), high sensitivity C-Reactive Protein (hsCRP), 25(OH)D, and routine hypercalcaemia
2. Three blood pressure measurements will be taken at each visit (first discarded and mean result of the following two will be used using an OMRON705CP sphygmomanometer accredited by the British Heart Foundation
3. Fasted urine samples will be collected in a willing sub-group of women and stored for future analysis of bone turnover markers
4. Adipose tissue distribution will be measured pre- and post-supplementation by dual energy x-ray absorptiometry (iDXA) full body scan

Secondary outcome measures

All primary and secondary outcomes will be measured at each study visit, i.e. at baseline, 2-, 4-, 6-, 8-, 10- and 12-month visits. Adipose tissue distribution will be measured at pre- and post-supplementation visits only.

1. Sunlight exposure will be assessed by a ultraviolet (UV) polysulphone film badge (3 cm in size) worn on the lapel of the outside coat or jacket for 7 days, which will monitor the amount of sunlight participants are getting in the following week
2. Diet will be assessed using a validated food frequency questionnaire to be completed at home
3. Physical activity level will be assessed using a validated physical activity questionnaire (which has already been used in other cohorts of post-menopausal women) to be completed at home
4. Grip strength will be assessed in a willing sub-group of women (as muscle strength may change depending on vitamin D status) using a grip strength dynanometer. The average of three readings will be taken.
5. Incidence of chronic pain will be assessed using a pain mannikin questionnaire

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

Women from a previous screening study (Aberdeen Prospective Osteoporosis Screening Study - APOSS) aged between 60 and 70 years.

Participant type


Age group




Target number of participants

300 (100 participants for each intervention arm: high vitamin D, low vitamin D, and placebo)

Participant exclusion criteria

Patricipants will be excluded if they:
1. Have been diagnosed with CVD
2. Have been diagnosed with diabetes
3. Have been diagnosed with asthma
4. Have high blood pressure (i.e. systolic blood pressure greater than 160 mmHg or diastolic pressure greater than 99 mmHg)
5. Suffer from chronic gastro-intestinal disease associated with malabsorption (e.g. coeliac disease, crohn's disease)
6. Are taking any medication regularly which might affect outcome measures such as hypotensive, hypolipemic, anti-inflammatory, or oral corticosteroid users

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Osteoporosis Research Unit
AB25 2ZD
United Kingdom

Sponsor information


University of Aberdeen (UK)

Sponsor details

Research and Innovation
University Office
King's College
AB24 3FX
United Kingdom
+44 (0)1224 272123

Sponsor type




Funder type


Funder name

Food Standards Agency (UK) (ref: N05R0015)

Alternative name(s)


Funding Body Type

private sector organisation

Funding Body Subtype

Other non-profit organizations


United Kingdom

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

1. 2012 results in:
2. 2013 results in:
3. 2013 results in:

Publication citations

  1. Results

    Wood AD, Secombes KR, Thies F, Aucott L, Black AJ, Mavroeidi A, Simpson WG, Fraser WD, Reid DM, Macdonald HM, Vitamin D3 supplementation has no effect on conventional cardiovascular risk factors: a parallel-group, double-blind, placebo-controlled RCT., J. Clin. Endocrinol. Metab., 2012, 97, 10, 3557-3568, doi: 10.1210/jc.2012-2126.

  2. Results

    Macdonald HM, Wood AD, Aucott LS, Black AJ, Fraser WD, Mavroeidi A, Reid DM, Secombes KR, Simpson WG, Thies F, Hip bone loss is attenuated with 1000 IU but not 400 IU daily vitamin D3: a 1-year double-blind RCT in postmenopausal women., J. Bone Miner. Res., 2013, 28, 10, 2202-2213, doi: 10.1002/jbmr.1959.

  3. Results

    Wood AD, Secombes KR, Thies F, Aucott LS, Black AJ, Reid DM, Mavroeidi A, Simpson WG, Fraser WD, Macdonald HM, A parallel group double-blind RCT of vitamin D3 assessing physical function: is the biochemical response to treatment affected by overweight and obesity?, Osteoporos Int, 2014, 25, 1, 305-315, doi: 10.1007/s00198-013-2473-8.

Additional files

Editorial Notes