GREYING OF HAIR is not an unusual thing to happen. The age when greying starts depends on one's genetic inheritance. Aging is often a reason that causes the hair to turn grayish. But premature graying of hair is a condition that demands the need to pay attention to the root cause. Nonetheless, greying of hair is a normal part of the aging process unless there is an underlying medical condition that is causing the lack of pigmentation. There are certain medical conditions that can cause greying of hair. These conditions are extremely rare and present themselves in less than one percent of the population but they do exist. The main symptom of this disease is the lack of regular thicker hair being allowed to grow. In turn, the thinner, grey hairs then have a chance to grow sooner and more rapidly than normal. The transformation is quick but it is not overnight.