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Why is vitamin B12 an important nutrient to consider in a vegan diet?

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Illustration of a vegan food pyramid divided into four sections: whole grains at the base, followed by vegetables, then fruit, and legumes at the top, with recommended daily servings and images of representative foods in each group. — vegetarianism A vegan food pyramid, which excludes meat and animal products.

Vitamin B12 (cobalamin) is a critical nutrient for humans because it is essential for DNA synthesis, the production of healthy red blood cells, and the maintenance of the myelin sheath that protects nerve fibers.21

Because vitamin B12 is found naturally only in animal-derived foods—such as meat, eggs, and dairy—it is a primary concern for those following a vegan diet. Without adequate intake, individuals are at risk of developing megaloblastic anemia, which can cause fatigue and weakness. More severely, a prolonged deficiency can lead to irreversible nerve degeneration, resulting in symptoms like numbness, tingling, and potentially paralysis.21

To maintain health, it is ethically and medically imperative that vegans ensure they obtain sufficient vitamin B12 through fortified foods or reliable supplements to prevent these serious neurological and hematological complications.21