Human Intervention Study to Increase 25-hydroxyvitamin D Levels (WeKo)

Human Intervention Study to Increase 25-hydroxyvitamin D Levels by Regular Consumption of Wheat Germ Oil (UV-treated) vs. Wheat Germ Oil Untreated (Control)

The interventional study will evaluate effectiveness and potential of a regularly consumption of wheat germ oil (UV treated) vs. wheat germ oil (UV untreated) to increase plasma vitamin D levels ín humans.

Study Overview

• Status: Completed
• Conditions: Vitamin D3 Deficiency
• Intervention / Treatment: Dietary supplement: Wheat germ oil (UV treated); Dietary supplement: Wheat germ oil (untreated)

Detailed Description

The interventional study in parallel design will evaluate the effectiveness and potential of a daily consumption of wheat germ oil (UV treated vs. untreated) to increase plasma vitamin D levels in humans.

Wheat germ oil is naturally rich in vitamin D precursors (ergosterol and 7-dehydrocholesterol), which are converted into vitamin D2 and vitamin D3 by a defined UV light irradiation for the present study.

Half of the participants will consume UV-treated wheat germ oil (intervention) and the other part will consume traditional wheat germ oil (untreated, control). The subjects will consume 10 ml of wheat germ oil per day over an entire period of 6 weeks (no follow-up).

On the basis of the planned human intervention study (randomized, single-blind, parallel design) it will be investigated to what extent a regular consumption of wheat germ oil (UV-treated) can contribute to the increase of plasma 25 (OH) D levels.

The comparison is made against the intake of traditional (untreated) wheat germ oil (control).

The study fits with the strategy of the Competence Cluster for Nutrition and Cardiovascular Health (nutriCARD), Halle-Jena-Leipzig, Germany (www.nutriCARD.de) and the study collaborators are active members of the nutriCARD cluster.

• Study Type: Interventional
• Enrollment (Actual): 50
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Germany
  • Thuringia
    • Jena, Thuringia, Germany, 07743
      • Friedrich-Schiller-University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• healthy subjects
• plasma 25(OH) vitamin D < 50 nmol/l
• nutritional habits: western diet

Exclusion Criteria:

• intake of lipid-lowering medications
• gastrointestinal diseases, diabetes mellitus type I and II
• intake of supplements (vitamin D supplements, fish oil capsules, vitamins and minerals) 3 months before and during the study
• relevant food allergies / intolerances
• visit to the solarium (within 4 weeks before beginning of the study and during the study)
• stay in the mountains / skiing (within 4 weeks before beginning of studies and during the study)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Wheat germ oil (UV treated)	Dietary supplement: Wheat germ oil (UV treated); Wheat germ oil is naturally rich in vitamin D precursors (ergosterol and 7-dehydrocholesterol), which are converted into vitamin D2 and vitamin D3 by a defined UV light irradiation for the present study (wheat germ oil (UV treated). The wheat germ oil (UV treated) is dispensed in dark glass bottles without label. The distinction between the groups is based on the expiration date (08.05.2018 vs. 09.05.2018). The distinction between the groups is not possible for the participants. The daily dosage of wheat germ oil is 10 ml and the study products will be consumed over an entire period of 6 weeks (no follow-up). Recommendation for intake: pure before a main meal.
Placebo Comparator: Wheat germ oil (untreated)	Dietary supplement: Wheat germ oil (untreated); commercial available wheat germ oil The wheat germ oil (untreated) is dispensed in dark glass bottles without label. The distinction between the groups is based on the expiration date (08.05.2018 vs. 09.05.2018). The distinction between the groups is not possible for the participants. The daily dosage of wheat germ oil is 10 ml and the study products will be consumed over an entire period of 6 weeks (no follow-up). Recommendation for intake: pure before a main meal.
No Intervention: Control; no study products

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Vitamin D status	plasma levels of 25OHD2, 25OHD3 (nmol/l)	change from baseline after 3 and 6 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood lipids	total cholesterol, LDL cholesterol, HDL cholesterol, triacylglycerides (mmol/L)	change from baseline after 3 and 6 weeks
Blood glucose	fasting blood glucose (mmol/l)	change from baseline after 3 and 6 weeks
Insulin	insulin (units/ml)	change from baseline after 3 and 6 weeks
soluble Klotho (sKlotho)	sKlotho is a component of the FGF23 system and is associated with longevity	change from baseline after 3 and 6 weeks
Fibroblast growth factor 23 (FGF23)	FGF23 is a regulator of vitamin D metabolism and also a risk factor for heart failure	change from baseline after 3 and 6 weeks
Fatty acid distribution (erythrocytes)	fatty acid distribution in erythrocyte lipids (% fatty acid methyl ester)	change from baseline after 3 and 6 weeks
Vitamin D forms 1	1,25(OH)2D2 (nmol/l)	change from baseline after 3 and 6 weeks
Vitamin D forms 2	1,25(OH)2D3 (nmol/l)	change from baseline after 3 and 6 weeks
Vitamin D forms 3	24,25(OH)2D (nmol/l)	change from baseline after 3 and 6 weeks
Vitamin D forms 4	20(OH)D (nmol/l)	change from baseline after 3 and 6 weeks

Collaborators and Investigators

• Sponsor: University of Jena
• Collaborators: Martin-Luther-Universität Halle-Wittenberg

Publications and helpful links

General Publications

• Bailer AC, Philipp S, Staudt S, Weidauer T, Kiehntopf M, Lorkowski S, Stangl GI, Dawczynski C. UVB-exposed wheat germ oil increases serum 25-hydroxyvitamin D2 without improving overall vitamin D status: a randomized controlled trial. Eur J Nutr. 2022 Aug;61(5):2571-2583. doi: 10.1007/s00394-022-02827-w. Epub 2022 Feb 27.

Helpful Links

• Study results

Study record dates

Study Major Dates

• Study Start (Actual): March 5, 2018
• Primary Completion (Actual): April 30, 2018
• Study Completion (Actual): April 30, 2018

Study Registration Dates

• First Submitted: March 29, 2018
• First Submitted That Met QC Criteria: April 13, 2018
• First Posted (Actual): April 17, 2018

Study Record Updates

• Last Update Posted (Estimate): February 22, 2023
• Last Update Submitted That Met QC Criteria: February 18, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: vitamin D; ergosterol; 7-dehydro-cholesterol; wheat germ oil
• Other Study ID Numbers: H5_18

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No