Reduced-fat Gouda-type cheese enriched with vitamin D3 effectively prevents vitamin D deficiency during winter months in postmenopausal women in Greece

Objective The primary aim of the present study was to examine the effectiveness of daily consumption of vitamin D-3-enriched, reduced-fat Gouda-type cheese on 25-hydroxyvitamin D (25(OH)D) concentration in postmenopausal women. Health-related quality of life (HRQL) indices were examined as secondary outcomes. Design This is a single-blinded (i.e., to study participants), randomized, controlled food-based dietary intervention study. Methods A sample of 79 postmenopausal women (55-75 years old) was randomized either to a control group (CG: n = 39) or an intervention group (IG: n = 40) that consumed, as part of their usual diet, 60 g of either non-enriched or vitamin D-3 enriched Gouda-type cheese, respectively, for eight consecutive weeks (i.e., from January to March 2015). Sixty grams of enriched cheese provided a daily dose of 5.7 mu g of vitamin D-3. Results There was a differential response of mean (95 % CI) serum 25(OH)D levels in the IG and CG, with the former increasing and the latter decreasing significantly over the eight weeks of the trial [i.e., by 5.1 (3.4, 6.9) nmol/L vs. -4.6 (-6.4, -2.8) nmol/L, P < 0.001, respectively]. The percentages of study participants with 25(OH)D levels <30 (deficiency) and <50 nmol/L (insufficiency) were significantly higher at follow-up in the CG compared to the IG (41.0 vs. 0 %, P < 0.001 and 74.4 vs. 47.5 %, P < 0.001, respectively). The emotional well-being scale of the HRQL score increased in the IG compared to a decrease in the CG (3.2 vs. -3.8, P = 0.028). However, none of the other seven scales of the HRQL score significantly differentiated between study groups (P > 0.1). Conclusions Consumption of 60 g of vitamin D-3-enriched, reduced-fat Gouda-type cheese provided a daily dose of 5.7 mu g of additional vitamin D-3 and was effective in increasing mean serum 25(OH)D concentration and in counteracting vitamin D deficiency during winter months in postmenopausal women in Greece.