Zinc

Zinc is an essential trace mineral involved in over 300 enzymatic reactions, including DNA synthesis, cell division, protein synthesis, and immune function. It plays a critical role in hair follicle biology, with zinc deficiency being a well-established cause of hair loss (particularly telogen effluvium and diffuse alopecia). Common supplemental forms include zinc picolinate, zinc gluconate, and zinc citrate, with varying bioavailability. Excessive zinc supplementation (>40 mg/day long-term) can induce copper deficiency.