Abstract
Intense public and scientific debate exists over whether the intake of some nutrients above the recommended dietary allowances may provide benefits beyond their traditional functions. However, excessive intakes of nutrients are well documented to cause adverse effects. This review focuses on methods that may be useful for identifying chronic intakes that result in adverse effects and for identifying intakes that provide a reasonable margin of safety from these effects. Groups responsible for nutrition and health policy must establish effective criteria for establishing safety limits, for validating end points, and determination of data acceptability. These criteria are needed to minimize toxicity while maximizing potential health benefits of exaggerated nutrient intake.