The prevalence and risk factors of vitamin D inadequacy among male athletes in Kuwait: A cross-sectional study

The aim of this study was to determine the prevalence of vitamin D inadequacy in male athletes living in Kuwait, and to assess its relationship with possible risk factors including body composition, lifestyle and fasting Ramadan. A Cross- sectional study was conducted on a total of 250 male athletes registered in official sports clubs in Kuwait were included. Blood tests, anthropometric measurements and a lifestyle questionnaire were performed. Serum 25(OH)D level was used as a measure of vitamin D status. Vitamin D inadequacy was defined as serum 25(OH)D < 75 nmol/L, inadequate levels were further classified as vitamin D insufficiency (50-75 nmol/L), vitamin D deficiency (<50 nmol/L) and severe deficiency (<25 nmol/L). Thirty-six percent of the sample were football players, 13% were futsal players and the rest were players of 15 different outdoor and indoor sports. A prevalence of 83% of vitamin D inadequacy (< 75 nmol/L) was observed in male athletes in Kuwait, of which 23% had severe deficiency (< 25 nmol/L). The prevalence increased from 80% (n = 130) before Ramadan to 90% (n = 79) after Ramadan. There was a significant positive association between serum 25(OH)D concentrations and vitamin D intake (p < 0.001). Serum 25(OH)D concentrations were significantly inversely associated with risk of injuries (p = 0.008) and with the concentrations of parathyroid hormone (PTH) (p = 0.029). No statistically significant associations between 25(OH)D concentrations and sun exposure, physical activity or anthropometric levels were found. Similar to other studies in the Middle East, we found that healthy male athletes in Kuwait have a high prevalence of vitamin D inadequacy. The results of this study suggest the need for regular supplement intake and vitamin D awareness campaigns for athletes in Kuwait. More research is needed to assess the effect of Ramadan.