Vitamin D-fortified cooking oil is an effective way to improve vitamin D status: an institutional efficacy trial

Purpose High prevalence of vitamin D deficiency (VDD) justifies a cost-effective and sustainable strategy to combat VDD in the community. This study was undertaken for the first time to evaluate the efficacy of daily consumption of vitamin D fortified sunflower oil with a meal. Methods This single-blind trial was conducted in two separate institutions: one as intervention (D-fortified sunflower oil) group (DO, n(1) = 39) and the other as control (unfortified sunflower oil) group (SO, n(2) = 33). Participants consumed their lunches cooked either with D-fortified or unfortified cooking sunflower oil (500 IU/30 g) for 12 weeks. Dietary, anthropometric and biochemical assessments were done for all participants before and after the intervention. Results A total of 65 subjects from both sexes aged 32.5 +/- 4 years completed the intervention period. Serum 25(OH)D showed a significant increase in DO and a decrease in SO group (8.8 +/- 9.3 vs. - 7.4 +/- 6.4 ng/mL, p < 0.001). The rise in serum 25(OH)D in DO group was accompanied by a significant decrease in iPTH (DO: - 10.2 +/- 29.4 vs. SO: + 9.2 +/- 29.5 pg/mL; p = 0.009). A significant reduction in weight (p = 0.004), BMI (p = 0.029), waist girth (p < 0.001), serum total cholesterol (p = 0.0290) and LDL-C (p = 0.010) was observed in DO, as compared with SO group. Conclusions Cooking oil can be considered as an efficacious vehicle for mass fortification program to combat VDD. The improvement of vitamin D status may bring about betterment of certain cardiometabolic risk factors. Registration number Clinicaltrials.gov: NCT03826654.