may include transporter proteins that provide homeostatic regulation of zinc intake and cellular processing.

• Information on the relationship of oxidative stress to zinc status; zinc is used therapeutically for treatment of some medical problems, but how this relates to daily dietary zinc intake is not clear.

• Effectiveness and potential toxicity of zinc as a dietary supplement; on which systems should zinc’s potential effectiveness be based, and which systems become dysfunctional with excessive zinc intake.

• The role of zinc and the immune system, particularly those related to T-cell function at marginal status.

• Quantitative data on human zinc homeostasis under a wide range of dietary conditions and at all ages using recent advances in zinc stable isotope methodology; quantification of what happens to zinc homeostasis as zinc intakes and absorption are increased and decreased beyond the range typically seen until recently; these metabolic studies need to be long-term.

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