Vitamin D deficiency is emerging worldwide and many studies now suggest its role in the development of several chronic diseases. Due to the low level of vitamin D naturally occurring in food there is a need for supplementation and use of vitamin D-enhanced products. The aim of the present study was to determine if daily consumption of vitamin D2-enhanced mushrooms increased vitamin D status in free-living healthy adults or affected markers of the metabolic syndrome. A total of ninety volunteers (aged 40-65 years) were randomly assigned to one of two 4-week studies: mushroom study (15 µg vitamin D2 or placebo mushroom powder) and capsule study (15 µg vitamin D3 or placebo capsules). Consumption of vitamin D2-enhanced mushrooms increased serum 25-hydroxyvitamin D2 (25(OH)D2) by 128 % from baseline (3·9 (sd 1·9) nmol/l; P < 0·05). Serum 25(OH)D3 increased significantly in the vitamin D3 capsule group (a 55 % increase from a baseline of 44.0 (sd 17·1) nmol/l; P < 0·05). Vitamin D status (25(OH)D) was affected only in the vitamin D3 group. Plasminogen activator inhibitor-1 was lowered by vitamin D2 intake. Vitamin D2 from enhanced mushrooms was bioavailable and increased serum 25(OH)D2 concentration with no significant effect on 25(OH)D3 or total 25(OH)D.
Keywords: 25(OH)D, 25-hydroxyvitamin D; Food enhancement; MetS, metabolic syndrome; Metabolic syndrome; Mushrooms; PAI-1, plasminogen activator inhibitor-1; PTH, parathyroid hormone; Vitamin D status; hsCRP, high-sensitivity C-reactive protein.