2024, Vol. 11, Issue 2, Part C

Vitamin D, an essential hormone, has gained attention for its potential impact on athletic performance and well-being. This study aimed to establish customized reference ranges of 25-hydroxyvitamin D (25(OH)D) for Indian athletes, considering factors such as gender, athletic disciplines, and indoor/outdoor sports. This study also assessed the prevalence of vitamin D deficiency or insufficiency among Indian athletes according to the standards set by the Endocrine Society and Institute of Medicine.

The study included 543 athletes (242 male, 301 female) from various sports in India. Standardized laboratory methods and questionnaires were used to assess 25(OH)D levels and to gather information on sunlight exposure, skin phototype, training experience, and dietary habits of the athletes. The 95% reference intervals for 25(OH)D levels among Indian athletes were calculated using Med Calc software 2016 according to CLSI guidelines C28-A3 and found to be 17.62-59 ng/mL, with slightly lower levels for females (15.1-58.8 ng/mL) compared to males (21.4-63.9 ng/mL). Indoor participants exhibited lower levels (13.8-79 ng/mL) compared to outdoor participants (18.1-63.4 ng/mL). These reference ranges closely align with the Institute of Medicine (IOM) standards. Based on IOM standards, Indian athletes exhibited a notably lower prevalence of vitamin D deficiency/insufficiency, with only 10% affected, in contrast to the guidelines of the Endocrine Society, which reported a higher prevalence of 37.7%.

These findings offer valuable insights into optimizing 25(OH)D levels for Indian athletes, aiding sports scientists, trainers, and nutritionists in evidence-based guidelines for preventing hypovitaminosis D and enhancing athletic performance and well-being.

These findings enable sports scientists, trainers, and nutritionists to accurately interpret the results, identifying suboptimal vitamin D levels in athletes. Consequently, these insights are valuable for optimizing 25(OH)D levels among Indian athletes, ultimately enhancing their performance and overall well-being.