Vitamin B12 is essential for numerous bodily functions, including red blood cell formation, neurological function, and DNA synthesis. Despite its importance, B12 deficiency is surprisingly common, particularly among older adults, vegetarians, vegans, and people with certain digestive conditions that affect nutrient absorption.
Symptoms of B12 deficiency can develop gradually and may include persistent fatigue, weakness, pale skin, shortness of breath, tingling in hands and feet, balance problems, and mood changes. Because these symptoms can be subtle initially, many people suffer from low-grade deficiency for months or years before seeking treatment.