Zinc is a trace mineral with a scientifically established role in supporting healthy hair growth and maintenance. Research indicates that zinc is essential for normal cellular function, hormone activity, and protein synthesis, all of which are necessary for the growth and repair of hair tissues. Several studies have demonstrated that zinc deficiency can lead to hair loss, particularly a condition called telogen effluvium, in which more hairs than usual enter the shedding phase. Supplementation with zinc has been shown to reverse hair loss in individuals who are deficient in this mineral.

However, while zinc supplementation is effective for individuals with a deficiency, evidence does not strongly support its use for improving hair health in those with adequate zinc levels. Excessive zinc intake can even lead to adverse effects, including impaired immune function and interference with the absorption of other minerals such as copper. The evidence for zinc’s role in treating common hair loss conditions like androgenetic alopecia (male or female pattern baldness) is limited and inconclusive.

Most clinical guidelines recommend evaluating zinc status in patients with unexplained hair loss and correcting any deficiencies. In summary, zinc's use in supporting hair health is justified by scientific evidence for specific cases of deficiency, but not as a general supplement for hair growth in the absence of deficiency.