Reference from the joint report of FAO/WHO expert consultation on Human Vitamins and Minerals verbatim.
32. AO/IAEA/WHO. 1996. Trace elements in Human nutrition and health. Geneva, World
Health Organization.
29. Simmer, K., Khanum, S., Carlsson, L. & Thompson, R.P.H. 1988. Nutritional rehabilitation in Bangladesh – the importance of zinc. Am. J. Clin. Nutr., 47: 1036-40.
13. Brown, K., Peerson, J.M. & Allen, L.H. 1998. Effects of zinc supplementation on children’s growth. In: Role of trace elements for health promotion and disease prevention. Sandström, B., Walter, P., eds. Bibliotheca Nutritio et Dieta, Basel: Karger; 54: 76-83.
The central role of zinc in cell division, protein synthesis, and growth makes infants, children, adolescents, and pregnant women especially at risk for an inadequate zinc intake. Zinc-responsive stunting has been identified in several studies (29), and a more rapid body weight gain in malnourished children supplemented with zinc was reported. Other studies have failed to show a growth-promoting effect of zinc supplementation (13).
A recent metaanalysis of 25 intervention trials comprising 1834 children under 13 years of age, with a mean duration of approximately 7 months and a mean dose of zinc of 14 mg/day (214 μmol/day), showed a small but significant positive effect of zinc supplementation on height and weight increases (13).
30. Black, M.M. 1998. Zinc deficiency and child development. Am. J. Clin. Nutr., 68(suppl.):464S-469S
The initial presence of stunting was significantly associated with an effect of zinc supplementation on height, whereas initial low plasma zinc concentrations were associated with a more pronounced effect on weight gain. Results from zinc supplementation studies suggest that a low zinc status in children not only affects growth but is also associated with an increased risk of severe infectious diseases (30).
31. Caulfield, L.E., Zavaleta, N., Shankar, A.H. & Merialdi, M. 1998. Potential contribution of maternal zinc supplementation during pregnancy to maternal and child survival. Am. J. Clin. Nutr., 68(suppl.): 499S-508S
Episodes of acute diarrhoea with shorter duration and less severity and reductions in incidence of diarrhoea in zinc-supplemented groups have been reported. Other studies indicate that the incidence of acute lower respiratory tract infections and malaria may also be reduced by zinc supplementation. Prevention of sub-optimal zinc status and zinc deficiency in children by an increased intake and availability of zinc could consequently have a significant effect on child health in developing countries.
The role of maternal zinc status on pregnancy outcome is still unclear. Positive as well as negative associations between plasma zinc concentration and foetal growth or labour and delivery complications have been reported (31). Results of zinc supplementation studies also remain inconclusive (31).
11. Agett P.J. & Favier A. 1993. Zinc. Int. J. Vit. Nutr. Res., 63: 247-316.
Interpretation of plasma zinc concentrations in pregnancy is complicated by the effect of hemodilution, and low plasma zinc levels may reflect other metabolic disturbances (11).
Zinc supplementation studies of pregnant women have been performed mainly in relatively well-nourished populations, which may be one of the reasons for the mixed results (31).
12. Goldenberg, R.L., Tamura, T., Neggers, Y., Copper, R.L., Johnston, K.E., DuBard, M.B. & Hauth, J.C. 1995. The effect of zinc supplementation on pregnancy outcome. JAMA, 274: 463-468
A recent study in low-income American women with plasma zinc concentrations below the mean at enrolment in prenatal care showed that a zinc intake of 25 mg/day resulted in greater infant birth weights and head circumferences and a reduction in very low birth weights among non-obese women compared with the placebo group (12).
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