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identified only about 30 papers that, even by a stretch of the imagination, could be used in revising or adding to the ULs. This presentation covers distinctions between risk and safety, several considerations for establishing ULs, data needs, and research needs.

Distinguishing Between Risk and Safety

To improve the process for setting ULs, it would be helpful to distinguish between risk and safety. Risk is an inherent property of a material. It depends upon exposure and a variety of factors, but it can be determined using scientific methods.

Safety, on the other hand, might be called a second order derivative of risk. Cultural, social, and other health reasons are used to decide what constitutes a safe dose. Safety must be defined, but it can be based on many factors other than scientifically based ones. Figure 10-1 illustrates this point.

In the DRI reports, the definition for UL is, “the highest level of daily nutrient intake that is likely to pose no risk of adverse health effects for almost all individuals in the general population.” Dr. Miller asserted that for some nutrients this is a virtual impossibility. To eliminate the risk, one must set a very, very low value for the UL. In fact, one needs to set the UL so low that the intake would not provide the positive nutritional benefits of the nutrient. The UL for vitamin D provides an example of this. Thus, Dr. Miller’s position is that the focus should be on acceptable risk, not no risk. Notably, ULs restrict dietary recommendations and regulatory policy options.

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