types of information about the individual, should be exercised when interpreting intakes below the AI.
Assessing individual diets for risk of adverse effects from excessive intake addresses the question, Given an individual's observed intake on a small number of days, is that individual's usual nutrient intake so high that it poses a risk of adverse health effects? The answer is obtained by comparing usual intake to the Tolerable Upper Intake Level (UL). A hypothesis test similar to the one proposed above for the AI can be used to decide whether usual intake is below the UL. For some nutrients, the intake to be considered is from supplements, fortificants, and medications only, while for other nutrients one may need to consider intake from food as well.
The UL is set at the highest level that is likely to pose no risk of adverse health effects for almost all individuals in the general population, including sensitive individuals; but it is not possible to know who is most sensitive. If usual intake exceeds the UL, it may pose a risk for some healthy individuals. The consequences of nutrient excess are much more severe for some nutrients than for others, and for some nutrients the consequences may be irreversible.
In all cases the individual's true requirement and usual intake can only be approximated. Thus, assessment of dietary adequacy for an individual is imprecise and must be interpreted cautiously in combination with other types of information about the individual.
What proportion of the group has a usual intake of a nutrient that is less than their requirement for the same nutrient? This is one of the most basic questions that can be asked about nutritional needs of a group, and is critically important from a public health perspective. Clearly, the implications are different if 30 versus 3 percent of individuals are estimated to be inadequate. Another basic question is, What proportion of the group has a usual intake of a nutrient so high that it places them at risk of adverse health effects?
The assessment of intake of groups requires obtaining accurate data on intake, selecting the appropriate Dietary Reference Intakes (DRIs), adjusting intake distributions for within-person variability