Effects of Vitamin D Supplementation on Testosterone, Prostate, and Lower Urinary Tract Symptoms: A Prospective, Comparative Study

Purpose: Several studies have associated the serum vitamin D level with total testosterone levels and the prostate volume. Herein, we investigated the effect of vitamin D supplementation on testosterone, prostate, and lower urinary tract symptoms (LUTS) in men. Materials and Methods: Men over 40 years of age diagnosed with a vitamin D deficiency (25[OH]D <20 ng/mL) who received vitamin D supplementation for one year were included in the study and administered 25,000 IU of cholecalciferol every 2 weeks. Prostate ultrasound, uroflowmetry, postvoid residual urine volume measurement, and serological tests (serum testosterone levels, etc.) were performed upon diagnosis and one year later. Participants also answered the International Prostate Symptom Score (IPSS) and Aging Males’ Symptoms Scale (AMS) questionnaires. Results: A significant increase was observed in the vitamin D level following one year of vitamin D supple-mentation, with a significant decrease in the postvoid residual urine volume, total IPSS score and without a significant change in the prostate volume. Improved psychological subscale score of AMS questionnaire was observed with a statistical significance. Conclusions: Vitamin D supplementation suppressed the increase in the prostate volume and improved the LUTS. Although there is no direct effect on serum testosterone levels, vitamin D supplementation helped improve hypogonadal symptoms.