Evidence check: B12 in the context of Sport

The provided context does not contain specific data or studies on vitamin B12 in sports. Generally, B12 is crucial for energy metabolism, red blood cell formation, and neurological function – a deficiency can impair athletic performance. However, the context lacks evidence for increased requirements in athletes or performance benefits from supplementation in non-deficient individuals. General literature shows moderate evidence: supplementation corrects deficiency-related declines, but no ergogenic effect in replete individuals. Since the context offers no sport-specific B12 research, the assessment remains conservative. Note: MyBody-X does not offer a dedicated B12 sport test; its nutrient deficiency test measures B12 but without sports interpretation. Evidence is rated as unclear.