Study design
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Participants were randomly allocated to the vitamin D supplement (n=22) or the placebo (n=22) groups utilizing a randomized block of size 4. A list of random numbers generated by Random Allocation Software (RAS) was used to allocate the participants. Researchers and patients were blinded to the treatments’ allocation. A general questionnaire was completed for all of the participants at the beginning of the study. The vitamin D group (n =22) received 50,000 IU/week of vitamin D and the control group (n =22) received a placebo containing sunflower oil for 12 weeks. Sunflower oil is one of the sources of vitamin E. However, the amount of vitamin E in one placebo pearl is negligible because the amount of vitamin E in one tablespoon of sunflower oil is 5.75 mg (