Background and Purpose: With increasing use of dietary supplements, including those containing nutrients, it is important to determine levels that may be safely consumed. The Council for Responsible Nutrition (CRN) previously derived upper levels (ULs) for supplemental intake for 28 nutrients. The objectives of the current work were: 1) to update the safety evaluation methodology to provide an enhanced systematic approach to identifying and evaluating available data and 2) to update or derive new ULs in healthy adults for 21 nutrient forms commonly consumed in dietary supplements based on this methodology (calcium, iron, magnesium, potassium, selenium, zinc, vitamin B6, vitamin E, menaquinone-7 (vitamin K2), vitamin A (pre-formed), lutein, zeaxanthin, meso-zeaxanthin, choline, citicoline, folic acid, methylfolate, nicotinic acid, nicotinamide, nicotinamide riboside, and inositol hexanicotinate). Methods: The CRN approach based on its principal points of departure for risk analysis was employed, which included a focus on human data from clinical trials (when available); direct evaluation of supplemental intakes (rather than total intakes, when possible); derivation of ULs based on true hazard (vs. nuisance effects); and conservative selection of human NOAEL values that justify selection of an uncertainty factor (UF) of 1.0. For each nutrient, systematic searching and screening of human clinical trials were performed. Data from epidemiological studies were assessed when necessary to evaluate a potential hazard or endpoint of concern. Studies meeting the inclusion criteria were reviewed and data extracted. The critical effect and associated toxicity value (e.g., NOAEL), if available, were identified. The supplemental UL was derived by application of UF(s) to the toxicity value. History of use data were used, if necessary, to identify a highest observed intake (HOI) when adverse effects in humans were not identified. Results: A standard operating procedure was developed to ensure systematic and transparent searching and screening of human clinical trials. Upper intake limits for nutrients derived by global regulatory and authoritative bodies were reviewed and summarized within each nutrient update for context. New or revised supplemental ULs/HOIs in adults were derived for all 21 nutrient forms. For example, the UL for vitamin B6 was maintained at 100 mg/ day based on human clinical studies in which no adverse effects occurred; excess vitamin B6 (pyridoxine) is associated with adverse neurological effects (e.g., neuropathy) at higher intake levels in human studies. Osmotic diarrhea related to unabsorbed magnesium was identified as the critical endpoint for magnesium. The UL for this nutrient was increased from 400 mg/day to 500 mg/day based on a lack of adverse effects in clinical trials at this dose; however, the magnesium UL does not apply to those with known risk factors related to kidney impairment. HOIs for three xanthophyll carotenoids were also derived based on the lack of any adverse effects across all clinical trials identified: lutein (22 mg/day), zeaxanthin (26 mg/day), and meso-zeaxanthin (17 mg/day). Conclusions: This work is part of an overall project to update supplemental ULs for 14 vitamins, 4 minerals, and 10 trace elements previously published by CRN, as well as newly derived supplemental ULs for additional vitamin forms and bioactives. These methods and the resulting ULs/HOIs are valuable tools for manufacturers to guide formulations and can be used internationally by policy makers and authoritative bodies in scientific discussions about setting upper intake levels for nutrients.