What effect does sodium hydroxide have on hair when used in relaxers?

Sodium hydroxide is an active ingredient commonly used in chemical relaxers, specifically designed for straightening curly or textured hair. When applied to the hair, sodium hydroxide breaks down the disulfide bonds that give hair its natural wave or curl. This alteration in the hair structure allows it to be straightened. The chemical's potency is what makes it effective in altering the hair's natural state, facilitating a permanent straightening effect.

Other options do not accurately represent the function of sodium hydroxide in relaxers. For instance, it does not enhance color or add volume, as its primary purpose is to chemically alter the hair structure rather than to add aesthetic features. Additionally, while some ingredients in hair products might nourish hair, sodium hydroxide is not aimed at nurturing or providing vitamins and minerals but rather at changing its structure. Thus, the primary and correct effect of sodium hydroxide in relaxers is inherently linked to its ability to straighten hair.