VERY RECENTLY I HAVE NOTICED THAT I HAVE GREY HAIR

VERY RECENTLY I HAVE NOTICED THAT I HAVE GREY HAIR AND THAT TOO QUITE A FEW. EARLIER, SAY ONE YEAR BACK I COULD NOTICE A SINGLE STRAND OF GREY HAIR WHICH I DINT PAY MUCH ATTENTION. BUT EVENTUALLY IT INCREASED IN NUMBER. NOW IF CAREFULLY OBSERVED ONE CAN FIND A CONSIDERABLE STRANDS OF GREY HAIR IN MY SCALP. I ALSO OBSERVED A STRAND OF GREY HAIR IN MY BEARD RECENTLY. I AM VERY WORRIED NOW. I CONSULTED A DOCTOR IN MY TOWN AND HE PRESCRIBED ALTRIS GEL AND SOME CALCIUM TABLETS. I AM APPREHENSIVE ABOUT THE LONG TERM EFFECT OF USING THE TABLETS, IN THIS REGARD COULD YOU PLEASE TELL IF I SHOULD CARRY ON WITH THE MEDICINE OR THERE IS SOME ALTERNATIVE YOU MIGHT SUGGEST. I HAVE NOT YET STARTED USING THE MEDICINE.