The symptoms of a b12 deficiency are disturbed vision, depression, irritability, mouth ulcers, feeling of pins and needles, sore and red tongue, pale yellow tinge to your skin and changes in the way that you walk and move around.
Other symptoms of a b12 deficiency are fatigue, breathlessness, numbness, poor balance, and memory trouble as well as anemia.
Also having a lack of vitamin b12 can cause anxiety in people who previously didn't have anxiety.
Besides causing anxiety having a lack of Vitamin b12 can also cause other psychiatric problems including panic attacks, depression and hallucinations.
When I suddenly started getting anxiety I went to the doctor about it and they said that I had a b12 deficiency so you certainly can have anxiety from having a lack of Vitamin b12.
So get checked out by the doctor if you suddenly start having anxiety or any other mentioned above things such as panic attacks, depression and hallucinations as well.
Since my vitamin b12 deficiency is not too severe I take supplements in pill form and changed my diet which is what the doctor suggested and it's working.
When the Vitamin b12 deficiency is more severe then you may need to take injections to treat the lack of Vitamin b12 deficiency.