Behavioral and hematologic consequences of marginal iron-zinc nutrition in adolescent monkeys and the effect of a powdered beef supplement

The adolescent growth spurt and menarche increase iron and zinc needs and could precipitate functional deficiencies if dietary sources are inadequate. The effects of mild, combined zinc and iron deprivation during the growth spurt and the ability of meat as a common dietary source of zinc and iron to reverse these effects was studied. Pubertal female rhesus monkeys were fed control diets (n = 8) or diets marginally deficient in zinc (2 microg/g diet; n = 8) and iron (10 microg/g diet; n = 8) for 3 mo. A powdered beef supplement (104 microg Zn/g and 43 microg Fe/g, 11 +/- 2 g/d) was then fed daily to half of the deprived group for 3 additional months. Growth and hematology were not affected significantly by iron-zinc deprivation, but plasma zinc and iron were somewhat lower in the deprived group than in the control group after 3 mo. The deprived monkeys reduced their participation in behavioral testing, responded more slowly and less frequently to test stimuli, and were less active. The beef supplement increased participation in testing and stabilized activity levels, but response times remained depressed. Plasma ferritin was lower in the nonsupplemented deprived monkeys than in the controls by the end of the experiment. Four of 8 of the deprived monkeys had iron deficiency anemia compared with none of the controls and 1 of 8 who received the beef supplement. Marginal zinc and iron deprivation in early adolescence can lead to behavioral and hematologic dysfunction in nonhuman primates and dietary beef supplements can prevent and reverse some of these effects.