Try our beta test site
IMPORTANT: Listing of a study on this site does not reflect endorsement by the National Institutes of Health. Talk with a trusted healthcare professional before volunteering for a study. Read more...

Vitamin D Inadequacy in Rural Populations, Evaluation of Correction by Food Supplementation

This study has been completed.
Information provided by (Responsible Party):
University of Wisconsin, Madison Identifier:
First received: January 7, 2008
Last updated: November 23, 2011
Last verified: November 2011
The purpose of the research is to describe vitamin D levels and bone status in a rural Wisconsin population. It is probable that individuals of varying age and ethnicity require different amounts of D to achieve optimal status. These likely scenarios will be explored in various populations. We hypothesize that the increase in serum 25(OH)D resulting from daily D3 ingestion is less pronounced with advancing age and different in Native than Caucasian Americans. In addition, the women in the middle age group, between the ages of 55 and 65, will have ultrasound tests completed to assess the impact of the Vitamin D supplementation on cardiovascular health.

Condition Intervention
Vitamin D Insufficiency
Vitamin D Deficiency
Dietary Supplement: Cholecalciferol (vitamin D3)

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Double Blind (Participant, Investigator)
Primary Purpose: Treatment
Official Title: Vitamin D Inadequacy: Documentation in Rural Populations and Evaluation of Correction by Food Supplementation (Phase III; Manitowoc Prevalence Study)

Resource links provided by NLM:

Further study details as provided by University of Wisconsin, Madison:

Primary Outcome Measures:
  • the primary outcome is the proportion of postmenopausal women with D inadequacy defined by current consensus as a serum 25(OH)D < 30 ng/ml. [ Time Frame: 2.5 years ]

Secondary Outcome Measures:
  • Prevalence of Vitamin D insufficiency in rural populations and ethnic differences in response to vitamin D supplementation [ Time Frame: 2.5 year ]
  • The relationship between vitamin D supplementation and cardiovascular disease. [ Time Frame: 2.5 Years ]

Enrollment: 108
Study Start Date: August 2007
Study Completion Date: August 2011
Primary Completion Date: August 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: 1 Dietary Supplement: Cholecalciferol (vitamin D3)
low calorie (~60 calories) cookie-like disc containing 2,500 IU of vitamin D3, taken by mouth daily for 4 months
Active Comparator: 2. 2500 IU vitamin D in a food preparation
Daily ingestion of 2500 IU vitamin D in a food preparation.
Dietary Supplement: Cholecalciferol (vitamin D3)
low calorie (~60 calories) cookie-like disc containing 2,500 IU of vitamin D3, taken by mouth daily for 4 months


Ages Eligible for Study:   55 Years and older   (Adult, Senior)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion criteria:

  • Healthy, community-dwelling ambulatory women.
  • Able and willing to sign informed consent.
  • Ages: 20-30, 55-65 or >75
  • Baseline serum 25OHD concentration > 10 ng/ml and < 60 ng/ml
  • Not pregnant
  • Willing to avoid use of cod-liver oil and non-study vitamin D supplementation; standard multiple vitamins containing ≤ 400 IU used no more than once daily will be allowed.
  • Willing to utilize sunscreen of SPF-15 or higher when sun exposure for more than 15 minutes is expected.

Exclusion criteria:

  • Current hypercalcemia (serum calcium > 10.5 mg/dl) or untreated primary hyperparathyroidism.
  • History of nephrolithiasis
  • Baseline 24-hour urine calcium > 250 mg
  • Known risk factors for hypercalcemia, e.g., malignancy, tuberculosis, sarcoidosis, Paget's disease.
  • History of any form of cancer within the past five years with the exception of adequately treated squamous cell or basal cell skin carcinoma.
  • Renal failure; defined as a calculated creatinine clearance (using the Cockroft-Gault approach) of ≤ 25 ml/minute.
  • Severe end-organ disease, e.g., cardiovascular, hepatic, hematologic, pulmonary, etc., which might limit the ability to complete this study.
  • Treatment with any drug known to interfere with vitamin D metabolism, e.g., phenytoin, phenobarbital.
  • Known malabsorption syndromes, e.g., celiac disease, active inflammatory bowel disease, etc.
  • Known allergy to chocolate.
  • Use of medications known to alter bone turnover including bisphosphonates, estrogen, selective estrogen receptor modulators, parathyroid hormone, testosterone or calcitonin.
  • Treatment with high dose vitamin D (≥ 50,000 IU weekly) or any active metabolites of vitamin D, e.g., calcitriol, within six months of screening.
  • Use of tanning beds or salons or unwillingness to utilize sunscreen during periods of sun exposure of 15 minutes or longer.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00690417

United States, Wisconsin
University of Wisconsin Osteoporosis Clinical and Research Program
Madison, Wisconsin, United States, 53705
Sponsors and Collaborators
University of Wisconsin, Madison
Principal Investigator: Neil Binkley, MD University of Wisconsin - Institute on Aging
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: University of Wisconsin, Madison Identifier: NCT00690417     History of Changes
Other Study ID Numbers: 2007-0211
Study First Received: January 7, 2008
Last Updated: November 23, 2011

Additional relevant MeSH terms:
Vitamin D Deficiency
Deficiency Diseases
Nutrition Disorders
Vitamin D
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents processed this record on April 27, 2017