People with B12 deficiency may feel short of breath or dizzy even during simple activities. This happens because a lack of B12 can impair red blood cell production, leading to anemia and improved oxygen levels.
8. Glossitis (swollen, inflamed tongue)
A B12 deficiency can cause the tongue to become sore, swollen, smooth, and inflamed. This is called glossitis and often leads to difficulty swallowing or speaking.
9. Vision problems
In some cases, a B12 deficiency can affect the optic nerve, causing vision problems such as blurred or double vision due to nerve damage.
10. Digestive problems
A B12 deficiency can cause digestive problems such as nausea, diarrhea, constipation, or loss of appetite.