Greying of Hairs

Greying is linked to pigment cells called melanocytes, Science reports.
Hair loses its colour and turns silver when cells that spawn melanocytes die off, the team from Boston's Dana-Farber Cancer Institute told the journal.
Melanocytes also go awry and multiply uncontrollably in deadly skin cancers so the team hopes the findings could lead to a way to stop tumour growth.
When black chromatophore is present in sufficient amounts, the hair is black. When black chromatophore is reduced over time through the aging process, the hair becomes grey. Further, if our hair cannot get enough nutrition from the blood from poor diet, stress etc., this will also cause graying of the hair.
Treatment

Dyeing is one of the most common ways of treating grey hair. Chemical dyes sold in the markets aid in coloring your hair. Though it is the most opted way, some people do not prefer it due to the reaction of its chemical properties on the hair and scalp.

Avoid foods loaded with artificial colors and preservatives, as these put a strain on your digestive system and can lead to dry brittle hair and a dehydrated scalp. Too many carbohydrates, such a pasta and bread, can diminish levels of antioxidants in your body that are needed to neutralize free radicals.
Ribbed gourd or torai, boiled in coconut oil is another effective remedy to prevent premature graying of hair. Pieces of these vegetables should be dried in the shade. These dried pieces should be soaked in coconut oil & kept aside for 3-4 days. The oil should be boiled till the solid is reduced to the blackened residue. This oil should be massaged into the scalp. It will help enrich the hair roots & restore pigment to the hair.

Soak about 10 to 12 rithas and 3 to 4 shikakai pods overnight in a pint of water. Next day, boil for a few minutes and strain. Use this liquid as a normal shampoo. Separately soak 10 to 12 dried amlas in half a cup of water overnight. Strain and use as a hair conditioner after your head bath. Leave it on the hair for ten minutes and rinse your hair with clean warm water. This will leave your hair smooth and shiny and also stop premature greying of your hair.

Minerals like zinc, iron & copper promote healthy hair. Food sources: zinc - red meat, chicken & green vegetables; iron - beef, dried apricots, red meat, parsley, eggs, wheat & sunflower seeds; copper - seafood, egg yolk & whole grains.

The use of Indian gooseberry is the foremost among the home remedies found beneficial in the prevention and treatment of premature greying of hair. This is a valuable hair tonic for enriching hair growth and hair pigmentation. The fruit, cut into pieces, should be dried, preferably in shade. These pieces should be boiled in coconut oil till the solid matter becomes like charred dust. This darkish oil is very useful against premature greying. The water in which dried amla pieces have been soaked overnight is also nourishing for the hair. This water should be used for the last rinse while washing the hair. Massaging the scalp every night with a teaspoonful of amla juice, mixed with a teaspoon of almond oil and a few drops of lime juice, also proves beneficial in the prevention and treatment of premature greying of hair.