Challenges in Achieving Adequate Vitamin D Status in the Adult Population - Part 1

NCT03818594 | Completed

• 1 other identifier: VITAD-01-2018 Part 1
• Study Type: observational
• Target: 338
• Locations: 1 country
• Sites: 1

Brief Summary

Seasonal variations in vitamin D status will be determined on a cohort of Slovenian adults using longitudinal study design, and association between vitamin D status and different Caucasian phototypes, skin colour and melanin index investigated .

Conditions

Vitamin D Serum Levels

Outcome Measures

Primary Outcomes (1)

• Difference between vitamin D serum levels in winter and in summer season will be determined

  Vitamin D serum level will be measured once in winter (December - January) and once in summer season (August-September) for each individual. The study will be performed over two consecutive years.

  2 years

Secondary Outcomes (3)

• Correlation of vitamin D serum levels with Fitzpatrick skin phototype

  2 years

• Correlation of vitamin D serum levels with skin colour measured in CIE Lab colour space

  2 years

• Correlation of vitamin D serum levels with melanin index

  2 years

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

General Slovenian adult population, men and women, skin phototypes I-IV.

You may qualify if:

• Signed Informed consent form (ICF),
• Caucasian race
• Age between 18 and 65 years at the time of the signature of Informed consent form (ICF),
• Willingness to avoid a consumption of any food supplements containing Vitamin D during the study, except the ones prescribed by the study researchers, and to avoid use of solarium or other artificial UVB sources
• Willingness to follow all study procedures

You may not qualify if:

• Pregnancy or breastfeeding,
• Known or suspected allergy to any ingredient of the tested products in Part 2,
• Pronounced avoidance of sunshine (eg reporting of allergy to the sun)
• Special dietary habits used by a small part of the population (veganism, low-carb hihg-fat diet, caloric restriction diet, note: vegetarians are not excluded)
• Diets prescribed by the medical profession
• Disorders of the kidneys, thyroid, digestive tract, osteoporosis and other bone diseases, skin diseases
• Other diseases and conditions that affect the absorption and synthesis of vitamin D
• Exposure to stronger sunlight in the last three months prior to engaging in a survey (travel to countries with stronger sunshine, use of solarium),
• The consumption of margarine or plant substitutes for milk / milk products several times a day, as these foods are most often enriched with vitamin D,
• Visiting the solarium in the last three months before joining the survey,
• Mental incapacity that precludes adequate understanding or cooperation.

Sponsors & Collaborators

• Institute of Nutrition, Slovenia (Nutris): lead
• VIST - Faculty of Applied Sciences: collaborator
• Slovenian Research Agency: collaborator
• Valens Int. d.o.o., Slovenija: collaborator

Study Sites (1)

Nutrition Institute, Ljubljana

Ljubljana, 1000, Slovenia

Location

Study Officials

• Katja Žmitek, PhD

  Researcher

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 17, 2019
• First Posted: January 28, 2019
• Study Start: January 8, 2019
• Primary Completion: September 28, 2020
• Study Completion: September 28, 2020
• Last Updated: June 18, 2021

Record last verified: 2021-06

Data Sharing

• IPD Sharing: Will not share

Locations

SL (1)