Vitamin D supplements raise footballers’ blood levels, but performance gains remain unclear
A review found that vitamin D supplements raised blood vitamin D levels in footballers but showed no consistent gains in performance tests. The evidence was low or very low certainty.
The review covered 11 reports from nine studies and 312 association football and futsal players. Vitamin D supplementation raised blood vitamin D levels, but pooled results showed no significant gains in jumping, sprinting, aerobic capacity or muscular performance.1
The review rated evidence as low for jump and muscular performance, and very low for sprinting and aerobic capacity. The authors said the small evidence base and low certainty called for caution.1
For trainers, the findings separate a rise in vitamin D status from evidence of improved performance. The review did not assess bone health, injury risk or long-term safety.1
