Known as anti-ophthalmic, vitamin A is essential for growth and vitality. It builds up resistance to respiratory and other infections and works on the eyes, lungs, stomach and intestines. It prevents eye diseases and plays a vital role in nourishing the skin and hair. It helps to prevent premature aging and senility, increases life expectancy and extends youthfulness.
The main sources of this vitamin are fish liver oil, liver, whole milk, curds, pure ghee, butter, cheese, cream and egg yolk, green leafy and certain yellow root vegetables such as Spanish, lettuce, turnip, beets, carrot cabbage and tomato and ripe fruits such as prunes, mangoes, papaya, apricots, peaches, almonds and other dry fruits.
A prolonged deficiency of vitamin A result in inflammation of the eyes, poor vision, frequent colds and night blindness and increased susceptibility to infections, lack of appetite and vigour, defective teeth and gums and skin disorders.
The recommended daily allowance of vitamin A is 5000 international units for adults and 2600 to 4000 international units for children. When taken in large therapeutic doses, which are usually 25000 to 50000 minutes a day, it is highly beneficial in the treatment of head and chest cold, sinus trouble, influenza and other infectious diseases. It is also valuable in curing night blindness and other eye diseases as well as many stubborn skin disorders. This vitamin can be given upto 1,00,000 units a day for a limited period of four weeks under doctors supervision.