What Happens to Your Body When You Have a Vitamin B12 Deficiency

Key Takeaways

Vitamin B12 deficiency can cause symptoms of anemia, nerve problems, and sensory changes that often resemble other conditions, making diagnosis difficult.

Most cases are due to low dietary intake or trouble absorbing B12. Diagnosis relies on a thorough medical history, a physical examination, and laboratory testing.

Treatment usually involves vitamin B12 supplements. An untreated deficiency can cause permanent symptoms and may require long-term rehabilitation.

Vitamin B12 deficiency is common in older adults, vegetarians, vegans, and people with certain medical conditions because the vitamin is mostly found in meat, fish, dairy, and fortified foods. When levels drop, symptoms like fatigue, headaches, muscle weakness, and depression can appear, but diagnosis can be tricky