Hi,
Thanks for posting your query.
Main important causes of graying of hair are vitamin B12 deficiency, autoimmune diseases and genetic conditions including vitiligo.
First consult a dermatologist to evaluate the cause.
Some Home remedies that are useful-
1.     Take healthy balanced and nutritious diet.
2.     Be sure to eat food XXXXXXX in protein, iron and iodine (very important for melanin synthesis) reach diet every day
3.     Stress reduction is an easy home remedy for graying hair.
4.     Add curry to your food and your hair. Eat lots of curry in condiments, sauces, or mixed with buttermilk.
5.     Try amaranth if you can find it (your best bets are Indian food stores). The fresh juice of the leaves of this vegetable as well as the grain varieties help hair to retain its natural color and prevent it from graying.
6.     Try ribbed gourd, which is said to enrich hair roots and restore pigment to hair.
7.     Mix one tablespoon of table salt (with iodine) into a cup of strong black tea (no milk). Massage into scalp and let sit for an hour before rinsing.

Hope I have answered your query. If you have any further questions I will be happy to help
If you do not have any clarifications, you can close the discussion and rate the answer and write a review.
Wish you good health.
Thanks,
Dr Sourav Ganguly

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