Influence of vitamin D supplementation on mental health in collegiate footballers

Introduction: Mental health in athletes has been gaining more attention in recent years. A strong association has been noted between vitamin D and psychiatric outcomes. This study examined the effects of six weeks of vitamin D supplementation on mental health among collegiate footballers. Methods: Thirtyone footballers (N=31; 18 males and 13 females) were recruited for the study. Serum 25(OH)D was measured to assess vitamin D and mental health was assessed using the Patient Health Questionnaire–9 (PHQ-9) and Generalised Anxiety Disorder-7 (GAD-7). Based on serum 25(OH)D levels, footballers were further categorised as (a) ‘deficient’ (<20.0 ng/mL), (b) ‘insufficient’ (21.0-29.9 ng/ mL), and (c) ‘sufficient’ (>30.0 ng/mL). The deficient and insufficient groups were given 60,000 IU cholecalciferol supplementation per week for six weeks and postintervention assessments were conducted. Paired t-test was used to ascertain the differences within groups. Results: Prevalences of vitamin D deficiency (48.0%), insufficiency (52.0%), depressive symptoms (13.0%), and anxiety symptoms (26.0%) were observed at baseline among footballers. Supplementation improved vitamin D levels from 20.7±5.4 ng/mL to 38.1±11.4 ng/mL (p<0.001). The rate of footballers with higher than cut-off scores for PHQ-9 and GAD-7 scores increased (32.3% and 29.0%, respectively) from baseline to post-intervention. Conclusion: Vitamin D supplementation enhanced serum 25(OH)D levels. However, no positive effects were noted regarding mental health symptoms. Additionally, changes in vitamin D levels might require more time to manifest observable effects on mental health.