Vitamin B Deficiency
Vitamin B complex
While vitamin A has received all the fame in eye health, it may come as a surprise that the B vitamins are an absolute necessity for good vision.
The vitamin B complex comprises a wide number of water-soluble vitamins, some with numbers and some with names.
Of the group the important ones for the eye are or thiamine and B2 or riboflavine and B12.
What is the effect of vitamin B1 deficiency? In what foods is it found?
Vitamin B1 or thiamine sources are:
(1) Whole cereal (whole grain and flour)
(2) Peas, beans and green vegetables
(3) Dairy produce
(4) Yeast and yeast extract.
Deficiency effects on the eye
(1) Retrobulbar neuritis (an affection of the optic nerve which affects transmission of vision and may lead to blindness).
(2) Change in the clarity of the membranes of the eye thus decreasing vision.
(3) Changes in the nerves of the eye.
The treatment is dosage with vitamin B1. Since it is a water-soluble vitamin, it is not stored for long and deficiency states can easily occur.
The maintenance dose is 1.0 mg per day.
What are the sources of vitamin B2 or riboflavine? What affect does deficiency have on the eye?
Deficiency leads to
(a) New vessel formation on the clear cornea of the eye which may lead to a marked fall in vision.
(b) Burning in the eye with misty vision, watering and sensitivity to light in the earlier stages.
The treatment is to give vitamin B2.
The maintenance dose is 1 mg per day.
What are the sources of vitamin B12? What effects does its deficiency have on the eye?
The food sources are meat, liver, eggs and milk as also other dairy products.
Deficiency of vitamin B12 can cause
(a) Optic neuritis or inflammation of the optic nerve, which if uncontrolled may lead to blindness in extreme cases.
(b) Changes in the nerves affecting the eye muscle, thus leading to partial squints.
The treatment is to give B12.
Vitamin C Deficiency
Ascorbic acid or vitamin C is a water soluble vitamin and is essential for development of bone and teeth, and for blood-forming tissues, healing of wounds and fractures and protection against infection.
(1) The food sources are fresh fruit and vegetables especially black currant and citrus fruits.
(2) Tomatoes, potatoes and cabbage.
Deficiency affects the eye through
(1) Haemorrhages (bleeding) from the socket and the lids of the eye, and retinal haemorrhages in extreme cases.
(2) Delayed healing of eye wounds and ulcers.
The treatment is vitamin C in high doses.
The maintenance dose in children is 30-50 mg per day and in adults, 80 mg per day.
Vitamin D Deficiency
Vitamin D (calciferol)
A fat-soluble vitamin essential for the normal development of teeth and bones and for the absorption of calcium and, indirectly, phosphorus.
(1) Eggs, liver, fish liver oil.
(2) Dairy produce—butter.
Vitamin D deficiency causes cataracts in the eye.
On the body in general, deficiency can cause rickets, bone deformations like bow legs, changes in bone formation of the chest (pigeon chest).
Dental changes include malformation and caries.
The maintenance dose is 400 I.U. per day.
What does excess of Vitamin D do to the body and the eye?
Since vitamin D is a fat-soluble vitamin, it can be stored in the body and excessive doses will cause accummulation leading to many symptoms.
In infants, excessive doses can cause a narrowing of the optic canals (bony. canals at the apex of the bony socket in the skull) through which passes the optic nerve, leading to progressive fall in vision.
In the eye, excess of vitamin D causes deposition of calcium on the front of the cornea of the eye, leading to marked fall in vision. Calcium deposits may also form on other parts of the eye leading to deleterious changes.
Thus, in summary, vitamins are essential for the eye, but in moderation. Excessive doses, given with misplaced zeal, can be harmful and should be avoided.