Anas was asked, "Did the Messenger of Allah ﷺ turn gray?"He replied, "Allah did not blemish him with gray hair. There were only seventeen or eighteen white hairs on his head and beard."
حدثنا عفان حدثنا حماد
قيل لأنس هل شاب رسول الله ﷺ قال ما شانه الله بالشيب ما كان في رأسه ولحيته إلا سبع عشرة أو ثمان عشرة
No references are available.
Its isnad is sahih, mentioned previously at 13012.