Premature greying means greying before the age of 35 years. If you have genes from your family that contain code for 'turning off' the metabolism of melanocytes at an early age, you will go grey at a rather young age.

Less blood supply to the hair follicles might also lead to greying. Early greying occasioned by genetic factors is known as Canities.

Another kind of genetically determined de-pigmentation of hair occurs in people who suffer from Albinism. Such people never produce any melanin in the skin and hair.

Since there is no melanin to protect them from the sun's harmful ultra-violet rays, people suffering from this disorder, must be careful not to expose themselves to the sun too much.

As mentioned earlier, our hair reflects our overall health. Imbalances within our body might show themselves in premature greying.

Disorder of the thyroid gland, particularly hyper- thyroidism, is associated with premature greying. It is also connected to Vitamin B12 Anemia (known as Pernicious Anemia) and Copper Deficiency Anemia. What we eat may affect the colour of our hair. Changes in hair colour due to protein deficiency are well recorded.

Occasionally, a hard knock to the scalp may cause a few strands of de-pigmented hair to grow. This phenomenon is known as Vitiligo and there is little that can be done to remedy it.