Deficiency

Vitamin B12 deficiency

Nerve and blood-cell effects from low B12, common in older adults due to reduced absorption rather than low intake.

Symptoms

  • numbness or tingling in hands/feet
  • fatigue
  • memory problems
  • balance issues
  • pale or jaundiced skin

These overlap with plenty of other conditions. Only a blood test can confirm a deficiency — treat this as a prompt to ask your doctor, not an answer.

What happens

Low Vitamin B12 impairs red blood cell formation (causing a form of anemia) and, if prolonged, can damage the myelin sheath protecting nerves — this second effect is why symptoms can include numbness, balance problems, and cognitive changes, not just fatigue.

Who’s at risk

Elderly adults are disproportionately affected: reduced stomach acid production impairs the release of B12 from food, even when dietary intake looks adequate on paper. People on long-term plant-based diets without fortification or supplementation are also at risk.

Dietary approach

Because the deficiency is often about absorption, not intake, addressing it may require a fortified food, supplement, or B12 injections rather than diet changes alone — worth a conversation with a doctor rather than self-diagnosis.

Citations

[1] NIH Office of Dietary Supplements — Vitamin B12 fact sheet.