Understanding Vitamin B12: Importance, Deficiency, and Sources

Vitamin B12, also known as cobalamin, is crucial for nerve tissue health, brain function, and red blood cell production. It's primarily found in animal products; thus, vegetarians are at higher risk of deficiency.

Early B12 deficiency symptoms include fatigue, weakness, constipation, loss of appetite, and weight loss. Advanced deficiency may cause neurological changes such as numbness and tingling in the hands and feet.

Beyond meat and dairy, lesser-known sources of B12 include nori seaweed, shiitake mushrooms, and fortified plant-based milks. These can be crucial for vegans to prevent deficiency.

B12 absorption requires proper stomach acid levels and intrinsic factor production. Issues like age-related decline or medications like PPIs can impair absorption, leading to deficiency despite adequate intake.

B12 deficiency is often diagnosed with blood tests measuring B12 levels, homocysteine, and methylmalonic acid. Elevated homocysteine and methylmalonic acid levels can indicate a deficiency before B12 levels drop.

Long-term B12 deficiency can cause irreversible damage to the brain and nervous system. It may mimic dementia, affecting memory, balance, and producing psychiatric symptoms, often confused with Alzheimer's disease.

Treatment involves B12 injections or high-dose oral supplements. Recovery depends on the duration and severity of the deficiency. Early treatment can lead to a complete reversal of symptoms.