Vitamin B12 is essential for healthy red blood cell formation, DNA production, and normal nervous-system function. Because the body stores relatively large amounts of B12, a deficiency may develop slowly and symptoms can take months or even years to become noticeable.
The difficulty is that early signs such as tiredness, weakness, poor concentration, or tingling can easily be blamed on stress, aging, or lack of sleep. Recognizing the possible warning signs matters because prolonged vitamin B12 deficiency can sometimes cause neurological problems that may not fully reverse if treatment is delayed.
Why Vitamin B12 Matters
Vitamin B12, also called cobalamin, plays several important roles in the body. It contributes to normal red blood cell production, neurological function, and DNA synthesis.
Unlike many nutrients, B12 is naturally concentrated mainly in animal-derived foods. Common dietary sources include meat, poultry, fish, eggs, and dairy products. Fortified foods can also provide B12, which is particularly important for people following vegan diets.
However, deficiency is not always caused by poor diet. Some people consume enough B12 but cannot absorb it properly.
1. Persistent Fatigue and Weakness
