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Impact of Work Environment Absent of Natural Light on Vitamin D Levels

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified June 2011 by Medical Corps, Israel Defense Force.
Recruitment status was:  Not yet recruiting
Information provided by:
Medical Corps, Israel Defense Force Identifier:
First received: June 28, 2011
Last updated: NA
Last verified: June 2011
History: No changes posted

Three types of workers exposed to different levels of natural sunlight will be tested for Vitamin D blood level, PTH, Ca, P, albumin and alkaline phosphatase.

In addition, each tested worker will be asked to fill a questionnaire for demographic, medical and personal habit information.

Vitamin D Deficiency

Study Type: Observational
Study Design: Observational Model: Case-Crossover
Time Perspective: Cross-Sectional
Official Title: Impact of Work Environment Absent of Natural Light on Vitamin D Levels

Resource links provided by NLM:

Further study details as provided by Medical Corps, Israel Defense Force:

Estimated Enrollment: 300
Study Start Date: November 2011
No natural sunlight
one group works in a basement with no natural sunlight
Low level of Natural Sunlight
the second group work in offices with unopenable windows.
High level of Natural Sunlight
The third group works outdoors.


Ages Eligible for Study:   18 Years to 45 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Probability Sample
Study Population
People employed in three types of natural sunlight exposure.

Inclusion Criteria:

  • people employed in their current work place at least 6 months,

Exclusion Criteria:

  • people who consume food additives containing Vitamin D.
  • people who have a chronic illness which harms the Vitamin D absorption, such as Celiac, chronic Pancreatitis, Cystic Fibrosis and IBS.
  • people who have a chronic illness which harms Vitamin D metabolism, such as chronic hepatitis, kidney insufficiency and Nephrotic Syndrome.
  • pregnant women.
  • people who require prescribed medicine like steroids, anti-convulsion, and HIV treatments.
  Contacts and Locations
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No Contacts or Locations Provided
  More Information

Responsible Party: Head of Industrial Hygiene, Occupational Medicine and Medical Classification Branch , IDF Identifier: NCT01385085     History of Changes
Other Study ID Numbers: 922-2010-IDF-CTIL
Study First Received: June 28, 2011
Last Updated: June 28, 2011

Keywords provided by Medical Corps, Israel Defense Force:
Vitamin D

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 28, 2017