This list, which is based on the transcript of the meeting, reflects suggestions made by presenters. It was prepared for the convenience of the reader. It should not be construed as representing recommendations or consensus statements.
Concentration of 25-hydroxyvitamin D—abbreviated as 25-(OH)D—needed for musculoskeletal end points/optimal circulating concentration
Standardization of 25-(OH)D assays
Better quantitation of the vitamin D content of foods
Potential problem of low phosphorus intake, especially by older individuals
Effect of the increasing use of calcium supplements on the bioavailability of phosphorous
Effect of anabolic agents for the treatment of osteoporosis on the need for phosphorus
Cataract production as a possible end point for setting the riboflavin Estimated Average Requirement (EAR)
Peripheral vascular disease function as an end point for niacin optimization
Genomic effects related to possible new indicators for setting an EAR for biotin
Possible adverse effects of pyridoxine (vitamin B6) supplementation on the inflammatory response
Possible adverse effects of unmetabolized folic acid in the serum
Consideration of genetic variation and relevant parameters in determining the need for individual recommendations for B vitamin requirements.
Selenoprotein P as a possible indicator for setting the EAR for selenium
Health risks associated with marginal selenium intake
Benefits of supplemental selenium as related to selenium status
Mechanisms responsible for selenium's health effects
The alpha-tocopherol, gamma-tocopherol, and delta-tocopherol contents of foods
Biological activity of various vitamin E forms in humans
The dose-dependence of carotenoid effects on health
Effects of polymorphisms on the efficacy of antioxidant nutrients
The role of oxidative stress in chronic disease development of biomarkers of oxidative stress
Relationships of increased risk for oxidative stress (caused by smoking, intense physical activity, high altitude, and genetic predisposition) to requirements for antioxidant nutrients
Predictive value of markers of oxidative stress for clinical end points
Subgroup effects, smoking especially, which persist for antioxidant nutrients
Should antioxidant nutrients be addressed more comprehensively for DRIs?
Risk and benefit curves for lutein, zeaxanthin, lycopene, and selenium chemical species and modulators for possible use in setting DRIs
Roles of vitamin K in coronary artery disease and in brain function
Human studies to examine links of neuropsychological outcome measures or other measures of cognitive function with vitamin K status
End points related to nutrient toxicity
Vitamin A and gene expression profiles
Bioavailability and metabolism of menaquinones, and the roles of menaquinones in vitamin K and sphingolipid metabolism
Classifications of iron-loading syndromes with identification of the central role of hepcidin
The relationship between iron status and infections such as HIV and tuberculosis
Status indices related to iron and cognition
Food-specific bioavailability questions
Biomarkers of zinc status, primarily genomic or proteomic, to correlate with functional outcomes such as immunity
The need, if any, for a Tolerable Upper Intake Level (UL) for functional fiber
The lowest levels of saturated fat, trans fat and cholesterol that are consistent with a healthy diet and that may cause a low but acceptable amount of harm
Mechanisms explaining why formerly obese persons may need 60 to 90 minutes of physical activity daily to maintain weight loss
Behavioral, environmental, policy, and other factors that help people adhere to a physical activity and exercise strategy to help maximize their potential for maintenance of weight loss
Consideration of differences in body composition and fat-free mass in studies related to energy
Effects of feeding functional fibers on measurements such as blood cholesterol, C-reactive protein, microflora, stool weight
Levels of intakes at which the onset of relevant health risks (e.g., obesity, coronary heart disease) occur
For persons with kidney dysfunction, the point at which potassium intake poses a risk for harm rather than benefit
Assessment of the protective effect of potassium-rich diets in blunting the adverse effects of sodium intake—basis for a recommended ratio of sodium intake to potassium intake
Analysis of breast milk, collected appropriately
Nutrient intake data (especially from complementary foods) related to biomarkers that are validated in children
Studies with stable isotopes and nanotracers to determine vitamin and mineral bioavailability, to investigate kinetics, and possibly to estimate change in pool size on different vitamin intakes
Doubly-labeled water studies to measure energy expenditure and water turnover
Determination of vitamin D requirements based on relationships of intake with 25-(OH)D, parathyroid hormone, bone markers, etc.
Translation of animal data to human health outcomes, which requires knowledge of the mechanisms
Chronic studies
Interactions of multiple nutrients and health end points
Risk/risk models that address the risks of two different materials in a single food and differences in the risks of a single nutrient under various circumstances
Sharper end points of adverse effects
Dose–response analyses with larger numbers
Depletion–repletion studies for adverse effects if feasible and ethical; otherwise, development of methods to obtain better information from cohort studies
Validated surrogate markers of risk
Relative importance of reducing the percentage of the population with inadequate intakes across the different nutrients
Health and statistical considerations in selecting targets for the percent inadequate across nutrients
Investigation of frequency questionnaires for systematic bias in intake estimates
Determination of dietitians’ methods of applying DRIs in their practices
Genotyping, epigenetics, and imprinting—including the assessment of effects of single nucleotide polymorphisms (SNPs) on variability in requirements and/or ULs
The use of first principles and discovering overlooked earlier findings
Studying monogastric farm animals, as to find surrogate measures for dose–response studies
Relationships of DRIs with long-term health
Use of genetics to help predict who will benefit from a specific dietary treatment
Use of metabolomics to distinguish individuals with a covert health problem from normal individuals and to analyze composition of food
Assessment of methods for determining individual risk of chronic disease outcomes
Delineation of specific genetic variants that contribute to wide interindividual variation in responses to dietary cholesterol and dietary fatty acids—considering low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides.
Identification of mechanisms whereby early nutritional experiences, such as dietary cholesterol and dietary fat intake, affect the atherosclerotic process and identification of the sensitive periods in development when this may occur.
Setting DRIs for children
Roles of genetic polymorphisms when revising DRIs
Differential responses, based on SNPs, to classical depletion– repletion studies
Development of a framework for establishing impacts and cutoffs for genetic variation that addresses two major points: (1) How prevalent do these polymorphisms have to be to warrant genotype specific recommendations? and (2) What is the penetrance—that is, what is the genetic contribution of variation compared to the overall variation requirement—and is that penetrance sufficient to warrant genotypic-specific results on which to base nutrient recommendations for subgroups?
A disease prevention approach that involves targeting the molecular antecedents of disease, such as molecular antecedents for cancer
If a nutrient has beneficial effects at doses much higher than needed for the prevention of deficiency, how should this affect the setting of EARs and RDAs?
If a nutrient prevents an adverse outcome in one subgroup but not in another, how can this information be incorporated into a DRI process?
Should the concept of a range of nutrient intake be reconsidered, or is there some other method to incorporate information about disease prevention (including subgroup-specific information) into the DRI process?
Development of a standard approach for setting an AI
Should an Adequate Intake (AI) be set for a nutrient that has no known essential functions in humans?
Can the process of setting ULs be made more systematic—one that consistently uses a decision tree approach?
Could risk assessment methodology be used to evaluate the lower end rather than just the upper end of nutrient risk?
New concerns for ULs related to epigenetic effects and genetic rescue
Can the UL concept be expanded to include a numerical value for nutrients for which an adverse effect or a toxicity has not been clearly established?
Are separate UL values needed for different forms of a nutrient?
Methods to apply the DRI process to chronic diseases
The meaning of “healthy population” in relation to setting DRIs
Setting ULs for nutrients for which there is a direct progressive relationship between intake and occurrence and/or severity of the adverse effect but for which there is no threshold
Criteria and methods for adjusting nutrient recommendations, as for age, size
A basis for expressing DRIs as densities or ratios
Consumer communication research