Micronutrients & recovery
Vitamin D supplementation (1000–5000 IU/day) prevents stress fractures in active populations by optimizing bone mineral density and calcium absorption.
If you are an athlete, especially indoors or in northern latitudes, get your Vitamin D levels checked. If you are deficient, supplement with 1000-5000 IU daily to reach optimal levels (>40 ng/mL). This helps prevent stress fractures, which can sideline your training. Aim for 15 minutes of sun exposure when possible, but don't rely on it exclusively if you avoid the sun.
In a large (n = 3700) vitamin D supplementation trial using female navy recruits, subjects receiving 800 IU/day of vitamin D for eight weeks, had a 20% lower incidence in stress fractures than the placebo group [8].
Why this rating
Supported by a large randomized controlled trial (n=3700) and consistent observational data, though generalizability to all sports varies.
Source
Vitamin D and the Athlete: Risks, Recommendations, and Benefits
Dana Ogan et al. · Nutrients · 2013
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