Muhammad bin Sirin (may Allah have mercy on him) says: I asked Sayyiduna Anas bin Malik (may Allah be pleased with him): Did the Messenger of Allah (peace and blessings be upon him) use dye? He said: The Prophet (peace and blessings be upon him) had very few white hairs.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب القسم والنشوز / 14813