Maintaining a healthy, balanced diet plays a huge role in the health of your hair, so making sure your body is getting all the hair-friendly vitamins and nutrients it needs can help to prevent white hairs.  Make sure you are eating plenty of lean protein (hair is made from protein), fruits, vegetables and whole grains. Drink plenty of water for hydration. More specifically, make sure you are getting enough of the vitamin B12 and the mineral zinc. If you don't feel you are getting enough in your diet naturally. Also make sure you are getting adequate amounts of vitamins A, C and E and of minerals like copper, iron and folic acid. Biotin (sometimes called vitamin H) is another important vitamin for healthy, naturally-colored hair. It is found in foods like cucumbers, oats and almonds. Poor quality hair products are full of chemicals such as sulfates, phosphates, chlorine and ammonia which dry out the hair and weaken the roots, making you more prone to white hairs. Therefore, you should stick to hair products with as many natural ingredients as possible. Head massages help to stimulate blood flow to the scalp, which keeps hair growing healthily. If possible, massage a natural oil like almond or coconut oil into the scalp, as this helps to deeply moisturize the hair roots. . According to one study, smokers are four times as likely to have white or grey hairs as their non-smoking counterparts. Smoking also causes hair to look dull and brittle and make it more prone to falling out. Melancor is a tablet-based product which rejuvenates natural hair color by stimulating the production of melanin in the hair follicles. It can help restore color to grey hair, and also prevent new grey hairs from forming. It needs to be taken once a day and has no common side effects. It can be purchased online. Note that there is no scientific evidence that Melancor works. You can try this supplement, but be aware of any side effects you may experience and understand that you may not get the results you hope for.

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Write a summary of the previous text in Vietnamese:
Áp dụng chế độ ăn giúp tóc khỏe mạnh. Tránh các loại mỹ phẩm tóc chất lượng kém. Mát-xa đầu thường xuyên. Ngừng hút thuốc. Uống thuốc Melancor.