Application of Risk Assessment: An Update of Safe Upper Limits (UL) of Essential and Nonessential Nutrients

The original method used by the Food and Nutrition Board (FNB) to establish tolerable upper intake levels (UL) for essential nutrients has significant limitations: no UL is identified without established toxicity, and the factor used to correct for uncertainty is quantitatively arbitrary. An extension of the UL method, first described as the Observed Safe Level (OSL) and more recently as the Highest Observed Intake (HOI), can be applied to nutrients, including many nonessential nutrients for which there are substantial data on safety of intake, but no established toxicity. With the accrual of newer human data and a significant regulatory and market need, both the FNB UL method and the OSL/HOI method were separately applied to two nutrients, vitamin D and coenzyme Q10. The former, an essential nutrient with recognized toxicity at sufficiently high intakes, and the latter, a nonessential nutrient, with no known toxicity. The uncertainty factor of 1.2 used by the FNB to calculate the 50 μg UL from a NOAEL of 60 μg for vitamin D was quantitatively arbitrary. There is sufficient confidence in the data now available to suggest a revised UL for vitamin D of 250 μg and to propose an OSL for coenzyme Q10 of 1200 mg. Uncertainty was managed by selecting data that warrant sufficient confidence that no quantitative correction is needed in identification of the UL, rather than identifying the highest non‐toxic intakes and correcting for uncertainty. No funding was specific to the preparation of this abstract. The salaries for authors were provided by the affiliated organization.