Is it permissible to dye white hair black when there is no suspicion of deception, and is there scholarly consensus on its prohibition or a difference of opinion, and is it permissible to adopt the view of those who permit it?

Dyeing hair black is prohibited for both men and women, based on the Prophet's (peace and blessings be upon him) saying: "Change this with something, but avoid black." The permissible alternatives are dyeing with henna and katam, or with any other color besides black. It is permissible to use materials to straighten curly hair, and this ruling applies equally to youth and elders, provided there is no harm and the substance is pure and permissible.