What to watch with B12 and Sport?

Vitamin B12 is crucial for red blood cell formation and energy metabolism, both important for athletic performance. Deficiency can cause fatigue, weakness, and anemia, impairing training and recovery. Athletes at higher risk include vegetarians, vegans, and those with gastrointestinal conditions (e.g., Crohn's, atrophic gastritis) or long-term use of acid-reducing medications. However, routine supplementation in individuals with adequate B12 levels does not enhance performance. A blood test (holotranscobalamin, MMA) is recommended before supplementing. Evidence for ergogenic benefit in non-deficient athletes is weak. Safety note: B12 is water-soluble, so excess is generally excreted, but high doses are unnecessary. The provided context does not directly address B12 and sport; this answer is based on established nutritional science.