Comparison of Bioavailability of Liposomal and Traditional Formulation of Vitamin D3

Comparison of Bioavailability of Liposomal and Traditional Formulation of Vitamin D3

The aim of the study was to compare the profiles of 25-hydroxyvitamin D serum concentration in healthy adults after 4 weeks of using vitamin D supplementation either in a liposomal or a traditional formulation.

The study will be randomized, cross-over, participants will be randomly assigned to one of the study groups: A) the group receiving vitamin D3 in traditional formulation B) the group receiving vitamin D3 in liposomal formulation. The day before the start of supplementation (T0), 2 weeks (T1) and 4 weeks (T2) after the start of supplementation, participants will have their blood drawn. Then, after a wash-out period of 2 months, the groups will be switched. Participants will again receive daily supplementation with vitamin D3 for 4 weeks. Blood will be drawn before the start of supplementation (T0), 2 weeks (T1) and 4 weeks (T2) after the start of supplementation.

Inclusion Criteria:

• Women and men, 18-60 years old.
• Signed informed consent.
• No injuries or hospitalizations within the last 3 months.
• No vitamin D supplementation for the 2 months prior to the study initiation.
• Refraining for the period of the clinical trial from consuming foods additionally fortified with vitamin D and dietary supplements containing vitamin D
• Refraining for the period of the clinical trial from the use of cosmetic therapies that use prolonged body illumination

Exclusion Criteria:

• Unwilling to give consent
• Injuries within the last 3 months
• Obesity, BMI above 30
• Bariatric surgery
• Cystic fibrosis, celiac disease, Crohn's disease
• Metabolic diseases
• Drugs reducing cholesterol absorption, thiazide diuretics, glucocorticosteroids, anticonvulsants, calcium-containing preparations,
• Planned prolonged exposure to sunlight during the study period