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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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Suggested Citation:"D Glossary and Acronyms." Institute of Medicine. 2006. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements. Washington, DC: The National Academies Press. doi: 10.17226/11537.
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PART IV: APPENDIX D 447 D GLOSSARY AND ACRONYMS AAP American Academy of Pediatrics ACC Acetyl-CoA carboxylase Accommodation An adaptative response that allows survival, but at the expense of some more or less serious consequences on health or physiological function ACE Angiotensin converting enzyme Action Demonstrated effects in various biological systems that may or may not have physiological significance Acute exposure An exposure to a toxin or excess amount of a nutrient that is short term, perhaps as short as one day or one dose. In this report it generally refers to total exposure (diet plus supplements) on a single day. Adaptation Maintenance of essentially unchanged functional capacity despite some alterations in steady-state conditions ADD Attention deficit disorder Adequacy of Intake of a nutrient that meets the individual’s nutrient intake requirement for that nutrient ADP Adenosine diphosphate Adverse effect Any significant alteration in the structure or function of the human organism, or any impairment of a physiologically important function, that could lead to an adverse health effect AI Adequate Intake; a category of Dietary Reference Intakes AITD Autoimmune thyroid disease AMDR Acceptable Macronutrient Distribution Range ANP Atrial natriuretic peptide Antioxidant See Dietary Antioxidant ARB Angiotensin II receptor blocker Association Potential interaction derived from epidemiological studies of the relationship between a specific nutrient and chronic disease ASTDR Agency for Toxic Substances and Disease Registry ATBC Alpha-Tocopherol, Beta-Carotene (Cancer Prevention Study)

DRIs: THE ESSENTIAL GUIDE TO NUTRIENT REQUIREMENTS 448 ATP Adenosine triphosphate AUC Area under the curve BEE Basal energy expenditure Bias Used in a statistical sense, referring to a tendency of an estimate to deviate from a true value (as by reason of nonrandom sampling). To be unbiased, a statistic would have an expected value equal to a population parameter being estimated. Bioavailability Accessibility of a nutrient to participate in unspecified metabolic or physiological processes BMI Body mass index BMR Basal metabolic rate CARET Carotene and Retinol Efficacy Trial Carotenodermia Yellow discoloration of the skin with elevated plasma carotene concentrations CDC Centers for Disease Control and Prevention; an agency of the U.S. Department of Health and Human Services CF Cystic fibrosis CHAOS Cambridge Heart Antioxidant Study CHD Coronary heart disease Chronic exposure Exposure to a chemical compound such as a nutrient for a long period of time, perhaps as long as every day for the lifetime of an individual CI Confidence interval CID Cold-induced diuresis CLAS Cholesterol Lowering Atherosclerosis Study Cluster analysis A general approach to multivariate problems, the aim of which is to determine whether individuals fall into groups or clusters CoA Coenzyme A Cr Elemental symbol for chromium CRBP Cellular retinol binding protein CSFII Continuing Survey of Food Intakes by Individuals; a survey conducted periodically by the Agricultural Research Service, U.S. Department of Agriculture Cut-point The exact point when something stops or changes. The EAR is used as a cut-point in the EAR cut-point method of assessing the prevalence of inadequacy for a group. CV Coefficient of variation—standard deviation divided by the square root of n, where n is the sample size CVD Cardiovascular disease; includes heart disease and stroke

PART IV: APPENDIX D 449 DASH Diet Dietary Approaches to Stop Hypertension Diet; a diet rich in fruits, vegetables, and low-fat diary products and reduced in saturated fat, total fat, and cholesterol DASH-Sodium Trial A clinical trial that tested the effects on blood pressure of three different sodium levels in two distinct diets DASH Trial A clinical trial that tested the effects of different dietary patterns on blood pressure DDS Delayed dermal sensitivity Deficiency An abnormal physiological condition resulting from inadequate intake of a nutrient or multiple nutrients. Dehydration The process of decreasing total body water; lower than normal total body water (euhydration) (see Hypohydration) DEXA Dual energy X-ray absorptiometry DFE Dietary folate equivalent DHA Docosahexaenoic acid Dietary antioxidant A dietary antioxidant is a substance in foods that significantly decreases the adverse effects of reactive species, such as reactive oxygen and nitrogen species, on normal physiological function in humans. Dietary status The condition of an individual or group as a result of food and nutrient intake. Dietary status also refers to the sum of dietary intake measurements for an individual or a group. Disappearance data Data that refer to food and nutrients that disappear from the marketplace. The term refers to food and nutrient availability for a population that is calculated from national or regional statistics by the inventory-style method. Usually taken into account are the sum of food remaining from the previous year, food imports, and agricultural production; from this sum is subtracted the sum of food remaining at the end of the year, food exports, food waste, and food used for non- food purposes. Disappearance data do not always take account of food that does not enter commerce, such as home food production, wild food harvests, etc. Distribution of observed The observed dietary or nutrient intake distribution intakes representing the variability of observed intakes in the population of interest. For example, the distribution of observed intakes may be obtained from dietary survey data such as 24-hour recalls. Distribution of The distribution reflecting the individual-to-individual requirements variability in requirements. Variability exists because not all individuals in a (sub) population have the same requirements for a nutrient (even if individuals are grouped into homogeneous classes, such as Hispanic men aged 19 to 50 years).

DRIs: THE ESSENTIAL GUIDE TO NUTRIENT REQUIREMENTS 450 Distribution of usual The distribution of long-run average dietary or nutrient intakes intakes of individuals in the population. The distribution should reflect only the individual-to- individual variability in intakes. Statistical procedures may be used to adjust the distribution of observed intakes by partially removing the day-to-day variability in individual intakes, so the adjusted distribution more closely reflects a usual intake distribution. DLW Doubly labeled water DNA Deoxyribonucleic acid Dose–response assessment Second step in a risk assessment in which the relationship between nutrient intake and an adverse effect (in terms of incidence or severity of the effect) is determined DRI Dietary Reference Intakes DTH Delayed-type hypersensitivity EAR Estimated Average Requirement; a category of Dietary Reference Intakes EAR cut-point method A method of assessing the nutrient adequacy of groups. It consists of assessing the proportion of individuals in the group whose usual nutrient intakes are below the EAR. ECF Extracellular fluid ECG Electrocardiogram EEG Electroencephalogram EEPA Energy expenditure of physical activity EER Estimated energy requirement EGR Erythrocyte glutathione reductase EGRAC Erythrocyte glutathione reductase activity coefficient EPA U.S. Environmental Protection Agency EPOC Excess post-exercise oxygen consumption Error in measurement Mistake made in the observation or recording of data Erythrocyte A red blood cell Euhydration Normal hydration FAO Food and Agriculture Organization of the United Nations FASEB Federation of American Societies for Experimental Biology FDA Food and Drug Administration; an agency of the U.S. Department of Health and Human Services Fe Elemental symbol for iron FFA Free fatty acids FFM Fat-free mass FM Fat mass FNB Food and Nutrition Board; a division of the Institute of Medicine of the National Academies

PART IV: APPENDIX D 451 Food balance sheet See Disappearance data Fore milk Human milk collected at the beginning of an infant feeding Former RDA and RNI Recommended daily dietary intake level of a nutrient sufficient to meet the nutrient requirement of nearly all healthy persons in a particular life stage and gender group. These standards were last issued in the United States in 1989 (RDA, Recommended Dietary Allowance) and in Canada in 1990 (RNI, Recommended Nutrient Intake). FQ Food quotient Function Role played by a nutrient in growth, development, and maturation GFR Glomerular filtration rate Gravid Pregnant H2O2 Hydrogen peroxide Hazard identification First step in a risk assessment, which is concerned with the collection, organization, and evaluation of all information pertaining to the toxic properties of a nutrient HDL High density lipoprotein Health Canada The federal department in Canada responsible for maintaining and improving the health of Canadian people Hind milk Human milk collected at the end of an infant feeding HIV Human immunodeficiency virus HOPE Heart Outcomes Prevention Evaluation Household Individuals sharing in the purchase, preparation, and consumption of foods. Usually this will represent individuals living as a family in one home, including adults and children. A household may be the unit of observation rather than the independent individuals within it. HPLC High-performance liquid chromatography HPV Human papilloma virus HRT Hormone replacement therapy Hyperhydration Higher than normal total body water (euhydration) Hyperkalemia Serum potassium concentration > 5.0 mEq/L or mmol/L Hypernatremia Serum sodium concentration > 145 mEq/L or mmol/L Systolic blood pressure ≥ 140 or diastolic blood pressure Hypertension ≥ 90 mm Hg Hypohydration Lower than normal total body water (euhydration) (see Dehydration) Hypokalemia Serum potassium concentration < 3.5 mEq/L or mmol/L Hyponatremia Serum sodium concentration < 135 mEq/L or mmol/L

DRIs: THE ESSENTIAL GUIDE TO NUTRIENT REQUIREMENTS 452 IAEA International Atomic Energy Agency IARC International Agency for Research on Cancer ICC Indian childhood cirrhosis ICCIDD International Council for the Control of Iodine Deficiency Disorders ICF Intracellular fluid ICT Idiopathic copper toxicosis IM Intramuscular Inadequacy of nutrient Intake of a nutrient that fails to meet the individual’s intake requirement for that nutrient Interindividual variability Variability from person to person Intraindividual variability Variability within one person. The term is generally used to refer to day-to-day variation in reported intakes, also called the within-person variation or standard deviation within (SDwithin). IOM Institute of Medicine IPCS International Programme on Chemical Safety IR Insulin receptor IRE Iron response element IRP Iron response proteins IU International unit Joint distribution Simultaneous distribution of both requirements (y-axis) and usual intakes (x-axis) for a single nutrient by individuals within a population or group Kashin-Beck disease Human cartilage disease found in some of the low- selenium intake areas in Asia Keshan disease Human cardiomyopathy that occurs only in selenium- deficient children Lacto-ovo-vegetarian A person who consumes milk (lacto), eggs (ovo), and plant foods and products, but no meat or fish LBM Lean body mass LCAT Lecithin-cholesterol acyltransferase LDL Low-density lipoprotein Likelihood Probability LMWCr Low molecular weight chromium-binding substance LOAEL Lowest-observed-adverse-effect level; the lowest intake (or experimental dose) of a nutrient at which an adverse effect has been identified LPL Lipoprotein lipase LSRO Life Sciences Research Office Lycopenodermia Deep orange discoloration of the skin resulting from high intakes of lycopene-rich food

PART IV: APPENDIX D 453 MAP Mean arterial pressure; diastolic pressure times 2 plus systolic pressure over 3; the average pressure during a cardiac cycle MCH Mean corpuscular hemoglobin—the amount of hemoglobin in erythrocytes (red blood cells) MCL Maximum contaminant level; a level set by the U.S. Environmental Protection Agency for environmental contaminants MCV Mean corpuscular volume—the volume of the average erythrocyte Mean intake Average intake of a particular nutrient or food for a group or population of individuals. Also average intake of a nutrient or food over two or more days for an individual. Mean requirement Average requirement of a particular nutrient for a group or population of individuals. MET Metabolic equivalent—a rate of energy expenditure sustained by a rate of oxygen consumption of 3.5 mL/kg of body weight/min MHC Major histocompatibility complex MI Myocardial infarction Mn Elemental symbol for manganese MPOD Macular pigment optical density MUFA Monounsaturated fatty acid MVP Mitral valve prolapse NAD Nicotinamide adenine dinucleotide NADH Nicotinamide adenine dinucleotide hydride; a coenzyme NADPH Nicotinamide adenine dinucleotide phosphate NAS National Academy of Sciences NE Niacin equivalent NEC Necrotizing enterocolitis NFCS Nationwide Food Consumption Survey; a food consumption survey conducted through 1965 by the U.S. Department of Agriculture NHANES National Health and Nutrition Examination Survey; a survey conducted periodically by the National Center for Health Statistics, Centers for Disease Control and Prevention NHIS National Health Interview Survey NO Nitric oxide NOAEL No-observed-adverse-effect level; the highest intake (or experimental dose) of a nutrient at which no adverse effect has been observed

DRIs: THE ESSENTIAL GUIDE TO NUTRIENT REQUIREMENTS 454 Normal distribution In the statistical sense, refers to a specific type of distribution of the values for a parameter within a group or population. The distribution is symmetrical and the mean ± 2 standard deviations will encompass the parameter for 95 percent of the individuals in the group. NRC National Research Council NTD Neural tube defect Nutrient requirement The lowest continuing intake level of a nutrient that will maintain a defined level of nutriture in a healthy individual; also called individual requirement Nutritional status Condition of an individual or group resulting from nutrient intake and utilization of a nutrient at the tissue level ORAC Oxygen radical absorbance capacity OTA Office of Technology Assessment Oxidative stress Imbalance between the production of various reactive species and the ability of the organism’s natural protective mechanisms to cope with these reactive compounds and prevent adverse effects OxLDL Oxidized low density lipoprotein PAI Physical activity index PAL Physical activity level 3¢-Phosphoadenosine-5¢-phosphosulfate PAPS Phylloquinone Plant form of vitamin K and a major form of this vitamin in the human diet PHS Physicians’ Health Study PL Pyridoxal PLP Pyridoxal phosphate PM Pyridoxamine PMP Pyridoxamine phosphate PN Pyridoxine PNP Pyridoxine phosphate Population A large group; in this report, a large group of people Prevalence The percentage of a defined population that is affected by a specific condition at the same time Prevalence of inadequate The percentage of a population that has intakes below intakes requirements Probability approach A method of assessing the nutrient adequacy of groups. It uses the distribution of usual intakes and the distribution of requirements to estimate the prevalence of inadequate intakes in a group. Also known as the NRC approach.

PART IV: APPENDIX D 455 Probability of inadequacy Outcome of a calculation that compares an individual’s usual intake to the distribution of requirements for persons of the same life stage and gender to determine the probability that the individual’s intake does not meet his or her requirement. a-Carotene, b-carotene, and b-cryptoxanthin Provitamin A carotenoids Psychogenic polydipsia The excessive consumption of fluid, especially water, among chronic psychiatric patients, particularly those with schizophrenia PUFA Polyunsaturated fatty acid RAR Retinoic acid receptor RBC Red blood cell RDA Recommended Dietary Allowance; a category of Dietary Reference Intakes RE Retinol equivalent REE Resting Energy Expenditure Requirement The lowest continuing intake level of a nutrient that will maintain a defined level of nutriture in a healthy individual Rhabdomyolysis Injury to skeletal muscle tissue that results in the destruction of skeletal muscle cells and allows for the escape of cellular contents into the extracellular fluid, leading to renal failure and compartment syndromes Risk The probability or likelihood that some unwanted effect will occur; in this report, refers to an unwanted effect from too small or too large an intake of a nutrient Risk assessment The organized framework for evaluating scientific information that has as its objective a characterization of the nature and likelihood of harm resulting from excess human exposure to an environmental agent (in this case, a nutrient); it includes the development of both qualitative and quantitative expressions of risk Risk characterization The final step in a risk assessment, which summarizes the conclusions from steps 1 through 3 of the assessment (hazard identification, dose response, and estimate of exposure) and evaluates the risk; this step also includes a characterization of the degree of scientific confidence that can be placed in the Tolerable Upper Intake Level Risk curve Used to demonstrate inadequacy or excess of a particular nutrient. As defined in the usual statistical sense, a risk curve is in contrast to the concept of probability curve.

DRIs: THE ESSENTIAL GUIDE TO NUTRIENT REQUIREMENTS 456 Risk management Process by which risk assessment results are integrated with other information to make decisions about the need for, method of, and extent of risk reduction; in addition, it considers such issues as the public health significance of the risk, the technical feasibility of achieving various degrees of risk control, and the economic and social costs of this control Risk of excess In relation to the DRIs, the likelihood that an individual will exceed the UL for a particular nutrient Risk of exposure In the toxicological sense, the likelihood that individuals will experience contact with a toxin (or consume levels of a nutrient above the UL) Risk of inadequacy The likelihood that an individual will have usual intake of a particular nutrient that is less than the individual’s requirement RMR Resting metabolic rate RNA Ribonucleic acid RNI Recommended Nutrient Intake RNS Reactive nitrogen species ROS Reactive oxygen species RQ Respiratory quotient RXR Retinoid X receptor Salt sensitivity The extent of blood pressure change in response to a reduction in salt intake; the term “salt-sensitive blood pressure” applies to those individuals or subgroups who experience the greatest reduction in blood pressure from a given reduction in salt intake SD Standard deviation SDA Specific dynamic action SE Standard error Selenite and selenate Inorganic selenium, the forms found in many dietary supplements Selenomethionine Major dietary forms of selenium and selenocysteine Selenosis Selenium toxicity characterized by hair loss and nail sloughing SEM Standard error of the mean Sensitivity analysis Technique of varying the implicit assumptions or presumed conditions of an analysis approach to see how much this affects the overall outcome SHRSP Stroke-prone spontaneously hypertensive (inbred strain of rats) Skewed distribution A distribution that is not symmetrical around its mean. For example, a skewed distribution can have a long tail to the right (right-skewed distribution) or to the left (left-skewed distribution).

PART IV: APPENDIX D 457 SMR Sleeping metabolic rate SOD Superoxide dismutase sTfR Soluble transferrin receptor Symmetrical distribution A distribution that has the same number of values (observations) above and below the mean and has equal proportions of these values around the mean TBW Total body water TDS Total Diet Study; a study conducted by the Food and Drug Administration a-TE a-Tocopherol equivalent TEE Total energy expenditure TEF Thermic effect of food Threshold The point in a dose–response curve that is accepted as the point beyond which a risk of adverse effects occurs TIBC Total iron binding capacity TMA Trimethylamine a-Tocopherol The only form of vitamin E that is maintained in human plasma and thus it is the only form utilized to estimate the vitamin E requirement Total water Includes drinking water, water in beverages, and water that is part of food Toxicity An adverse condition relating to or caused by a toxin TPN Total parenteral nutrition TPP Thiamin pyrophosphate TRH Thyrotropin-releasing hormone True prevalence The actual prevalence of a condition assuming no error in measurement of either requirements or intakes that would result in false negative or false positive classifications TSH Thyroid stimulating hormone, also known as thyrotropin a-TTP a-Tocopherol transfer protein UF Uncertainty factor; the number by which the NOAEL (or LOAEL) is divided to obtain the Tolerable Upper Intake Level; the size of the UF varies depending on the confidence in the data and the nature of the adverse effect UL Tolerable Upper Intake Level; a category of Dietary Reference Intakes Unit of observation The level of aggregation at which data are collected. For example, the unit of observation for dietary assessment may be the individual, the household, or the population Univariate distribution The distribution of a single variable USDA U.S. Department of Agriculture USP U.S. Pharmacopeia

DRIs: THE ESSENTIAL GUIDE TO NUTRIENT REQUIREMENTS 458 Usual intake The long-run average intake of food, nutrients, or a specific nutrient for an individual Variance of usual intakes In the statistical sense, reflects the spread of the or requirements distribution of usual intakes or requirements on both sides of the mean intake or requirement. When the variance of a distribution is low, the likelihood of seeing values that are far away from the mean is low; in contrast, when the variance is large, the likelihood of seeing values that are far away from the mean is high. For usual intakes and requirements, variance reflects the person-to-person variability in the group. The 2R-stereoisomeric forms of a-tocopherol (RRR-, Vitamin E RSR-, RRS-, and RSS-a-tocopherol) VLDL Very low density lipoprotein WHO World Health Organization

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Widely regarded as the classic reference work for the nutrition, dietetic, and allied health professions since its introduction in 1943, Recommended Dietary Allowances has been the accepted source in nutrient allowances for healthy people. Responding to the expansion of scientific knowledge about the roles of nutrients in human health, the Food and Nutrition Board of the Institute of Medicine, in partnership with Health Canada, has updated what used to be known as Recommended Dietary Allowances (RDAs) and renamed their new approach to these guidelines Dietary Reference Intakes (DRIs).

Since 1998, the Institute of Medicine has issued eight exhaustive volumes of DRIs that offer quantitative estimates of nutrient intakes to be used for planning and assessing diets applicable to healthy individuals in the United States and Canada. Now, for the first time, all eight volumes are summarized in one easy-to-use reference volume, Dietary Reference Intakes: The Essential Reference for Dietary Planning and Assessment. Organized by nutrient for ready use, this popular reference volume reviews the function of each nutrient in the human body, food sources, usual dietary intakes, and effects of deficiencies and excessive intakes. For each nutrient of food component, information includes:

  • Estimated average requirement and its standard deviation by age and gender.
  • Recommended dietary allowance, based on the estimated average requirement and deviation.
  • Adequate intake level, where a recommended dietary allowance cannot be based on an estimated average requirement.
  • Tolerable upper intake levels above which risk of toxicity would increase.
  • Along with dietary reference values for the intakes of nutrients by Americans and Canadians, this book presents recommendations for health maintenance and the reduction of chronic disease risk.

Also included is a "Summary Table of Dietary Reference Intakes," an updated practical summary of the recommendations. In addition, Dietary Reference Intakes: The Essential Reference for Dietary Planning and Assessment provides information about:

  • Guiding principles for nutrition labeling and fortification
  • Applications in dietary planning
  • Proposed definition of dietary fiber
  • A risk assessment model for establishing upper intake levels for nutrients
  • Proposed definition and plan for review of dietary antioxidants and related compounds

Dietitians, community nutritionists, nutrition educators, nutritionists working in government agencies, and nutrition students at the postsecondary level, as well as other health professionals, will find Dietary Reference Intakes: The Essential Reference for Dietary Planning and Assessment an invaluable resource.

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