ExtractConcentrations of zinc in hair were determined for 338 apparently normal subjects living in Denver with ages ranging from 0-40 years. Mean concentrations of zinc in hair were: neonates (25) 174 db 8 (1 SEM); 3 months^-years (93) 88 ± 5; 4-17 years (132) 153 ± 5, and 17^0 years (88) 180 ±4. Ten children more than 4 years of age had levels of zinc in hair of less than 70 ppm. Seven of these ten children had a history of poor appetite and eight had heights on or below the 10th percentile; the high incidence of low growth percentiles was not explicable on a familial basis. Taste acuity was tested in six of these children, and five had evidence of obj ective hypogeusia. After supplementing the diet with small quantities of zinc, taste acuity was normalized in each of these children and levels of zinc in hair increased. Speculation