Vitamin B12 is very important as it’s vital for many processes in the body. Not getting enough can be detrimental to a person’s health. If the body lacks the vitamin it will fail to make enough red blood cells, or the blood cells will become abnormally large. If red blood cells are in short supply, then symptoms of anaemia can be triggered. One symptom of vitamin B12 deficiency which researchers have shown is important to note is blurry visionAnaemia is a condition that can lead to heart and lung problems, and the heart can struggle to pump oxygen to vital organs.One symptom of vitamin B12 deficiency which researchers have shown is important to note is blurry vision.Blurry vision can occur when untreated B12 deficiency causes nervous system damage to the optic nerve that leads to your eyes.This was the finding of a study titled ‘B12 deficiency with neurological manifestations in the absence of anaemia’.The damage can play havoc on the nervous signal that travels from the eye to the brain, therefore impairing vision.Optic neuropathy is the medical term for this condition.Vitamin B12 deficiency symptoms: A sign in your eyes that could signal the condition (Image: GETTY)Other symptoms of vitamin B12 deficiency are listed by Bupa: Feeling very tiredBreathlessness even after little exerciseHeart palpitationsHeadachesA reduced appetiteA sore mouth and tongueVitamin B12 deficiency symptoms: Blurry vision could be a sign of the condition (Image: GETTY)Vitamin B12 deficiency symptoms: A headache could also be a sign you’re lacking the vitamin (Image: GETTY)The health organisation adds: “If you have vitamin B12 deficiency you may also look pale or jaundiced (have a yellowy tinge to your skin and the whites of your eyes).”Damage to the nerves caused by vitamin B12 deficiency may also affect your movement and sensation, especially in your legs, cause numbness or pins and needles and decrease your sensitivity to touch, vibration or pain.This could also cause confusion, depression, poor concentration and forgetfulness.Vitamin B12 is best gained through diet, with adults requiring 1.5mg a day.Here are six vitamin B12-rich foods you should consider eating to avoid the development of vitamin B12 deficiency.