Low vitamin B12 can affect thinking and mental clarity. Some people feel forgetful, slow, confused, or mentally foggy. They may struggle to focus, remember words, or keep track of tasks.
This can be frightening, especially in older adults, because it may be mistaken for dementia. But vitamin B12 deficiency is one of the health problems doctors may check when someone develops memory or thinking changes.
MedlinePlus notes there is no evidence that B12 supplements prevent or treat dementia in people who are not deficient, but B12 deficiency itself can cause serious symptoms and needs proper treatment.
6. Mood Changes, Depression, or Irritability
Vitamin B12 deficiency can also affect mood. Some people experience depression, irritability, anxiety, personality changes, or emotional instability.
Cleveland Clinic explains that vitamin deficiency anemia can cause depression, and severe vitamin B12 deficiency may cause confusion, forgetfulness, or personality changes.
Mood changes do not always mean B12 deficiency. They can come from stress, grief, sleep problems, depression, medication effects, or many other conditions. But when mood changes appear with fatigue, tingling, balance problems, or memory issues, B12 should be considered.
7. Sore Tongue or Mouth Problems
