How can I get my black hair color back?

Hair has the highest zinc concentration in the body. RDID19518.

In 1-12 year old boys they found a range of zinc / copper ratios in shades of brown hair
In black hair there was significantly more zinc.

Zinc supplements: RDID508

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J Nutr. 1983 Nov;113(11):2375-81.

The influence of hair color on the concentration of zinc and copper in boys' hair.


Head hair of 150 normal boys from Brazil ranging in age from 1 to 12 years was studied for the influence of color on concentrations of zinc and copper. Hair color was classified visually and also quantified by melanin concentration. Visual classification and spectrophotometric measurements of melanin showed good agreement for blond and black colors, whereas large discrepancies were observed for intermediate colors such as light and dark brown. Hair distributed in four ranges of melanin concentration (the numerical estimate of color) showed no significant differences for concentration of Zn and Cu but showed a significantly higher (P less than 0.01) concentration for Zn:Cu in black hair than in the other color groups. Correlation between mineral content (Zn and Cu) and melanin was low and nonsignificant except for Zn in hair color ranging from 0-100 melanin units (r = -0.34, P less than 0.05). Discussion of these findings is presented regarding the importance of hair color change in children and estimation of mineral nutritional status.