and it depends on the condition of the digestive tract, the quantity eaten, the degree of the body's saturation, and the presence of other substances in the intestines.

Vitamin A is stored in the liver, the kidney, and the lung, but the liver is its greatest storehouse, containing about 35% of the store.

The need for it: The quantity it is advisable for an adult person to take daily is 5,000 international units, and this quantity is increased in cases of illness, rapid growth, pregnancy, and nursing.

Its sources: Green and yellow vegetables and yellow fruits are rich in vitamin A. Among these vegetables are carrots, chard, spinach, endive, mulukhiyyah, mint, parsley, green broad beans, cress, and others; and among fruits, peaches and apricots. Among its rich sources also are butter, cream, cheese, eggs, milk, liver, and fish oil.

Its deficiency: Its deficiency harms the body and works changes in it: it obstructs growth and disturbs reproduction; the eye is affected and loses its luster, the eyelids grow congested and swollen, the secretion of tears diminishes, and the cornea softens, which leads to invasion by germs and even to blindness. This disease is called the disease of dryness of the eye, xerophthalmia. Among the ailments of the eye also is night blindness, that is, the inability to see by night, the eye being unable to adjust itself in the dark. So too the nervous system changes, the spinal cord degenerates, and the great muscles stiffen. Nor does the harm stop at this limit: the skeletal muscles degenerate, the bones become brittle and quickly damaged, and the spleen, the liver, and the bone marrow lose their power to grow. The

deficiency of this vitamin causes diseases of the pancreas and various kinds of infections such

as colds, and pulmonary diseases such as tuberculosis.