determine if a significant or unreasonable risk of illness or injury exists when consuming a nutrient as a dietary supplement at its suggested level of intake. This is the integrative evaluation component.

An integrative evaluation should use as its basis the DRI review and analysis, recognizing that for some nutrients (i.e., vitamin K, β-carotene, arsenic, chromium, silicon, thiamin, riboflavin, vitamin B₁₂, pantothenic acid, biotin, potassium, and sulfate) the available data, while reviewed in the DRI series, were deemed insufficient to develop a UL based on requirements of the model of risk assessment used. This does not indicate that high intakes pose no risk of adverse effects (IOM, 1998a, 2000, 2001, 2004), but that a thorough review by an expert group could not identify dose- response evidence from chronic intakes that would provide a basis for establishing the level at which adverse effects might occur.

If a UL was not established for the vitamin or mineral element under question, it is important to consider the following:

• Was the substance reviewed by the DRI process, even if a UL was not established?

• Is there new evidence suggesting risk that was not available at the time of the DRI review?

• Was significant concern about serious harm expressed in the DRI review, even if a DRI could not be established because of limits in the data or acuteness of the adverse effect (e.g., arsenic)?

It is assumed that the integrative evaluation for a nutrient would contain the same general components as for other dietary supplement ingredients, with the exception that significant information is already captured by virtue of the DRI process and its reports. In situations where new data or information indicate that higher concern is warranted, the nutrient would enter the evaluation in the same manner as other supplement ingredients. Nutrients are usually well-characterized chemically and thus there is less concern about active ingredient identification and function.

In evaluating evidence indicating that an ingredient may present an unreasonable risk to human health, a comprehensive examination of the literature is required, recognizing that not all studies are relevant to ascertaining the safety of a dietary supplement ingredient. The initial step in