Vitamin B12
Essential for red blood cell formation and nerve function. Plant-based athletes at high risk.
Why it matters
Vitamin B12 (cobalamin) is essential for red blood cell formation, neurological function, and DNA synthesis. It works alongside folate in producing healthy red blood cells and maintaining the myelin sheath that protects nerve fibres. B12 is found almost exclusively in animal products, making deficiency common in plant-based eaters and older adults (who absorb it less efficiently).
For endurance athletes
B12 deficiency develops slowly stores can last years but once depleted, it causes macrocytic anaemia, fatigue, impaired nerve function, and reduced red blood cell production. All of these directly impair endurance performance. Plant-based athletes should supplement B12 routinely. Omnivores who are consistently fatigued with no other explanation should have B12 levels tested.
Signs of deficiency
- ·Fatigue and weakness
- ·Numbness or tingling in hands and feet
- ·Difficulty concentrating
- ·Pale or yellowish skin
Best food sources
- ·Meat, poultry and fish
- ·Dairy and eggs
- ·Fortified plant milks and cereals
- ·Nutritional yeast (fortified)
- ·B12 supplements (essential for plant-based athletes)
Track Vitamin B12 automatically
MOVE logs micronutrients from every food you eat and shows sport-specific context alongside your numbers.