Two connected systems
B12 matters for both nerves and blood cells. That does not mean every tingling sensation or episode of fatigue is a deficiency.
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Vitamin B12 supports nerve cells, red blood-cell formation and DNA production.
B12 matters for both nerves and blood cells. That does not mean every tingling sensation or episode of fatigue is a deficiency.
Follow the sourceA stomach protein called intrinsic factor helps the body absorb B12.
Follow the sourceAnimal foods naturally provide B12. People eating few or no animal foods need reliable fortified foods or another suitable source.
Follow the sourceB12 supplements do not boost energy or endurance in people who already get enough.
Deficiency can involve neurological symptoms as well as anaemia. Suspected deficiency needs assessment; metformin and acid-suppressing medicines can affect B12 status.
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