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Using Dietary Reference Intakes in Planning Diets for Inclivicluals SUMMARY The goal of planning a cliet for an incliviclual is to achieve a low probability of inadequacy while not exceeding the Tolerable Upper Intake Level (UL) for each nutrient. The Recommencleci Dietary Allowance (RDA) or Acloquate Intake (AI) is used as the target nutrient intake for inclivicluals, and planners should realize that there is no recognized benefit of usual intakes in excess of these levels. Fooci-baseci nutrition education tools are regularly used to help an incliviclual plan a healthy cliet. However, as a result of the evaluation of new ciata regarding nutrient requirements presented in the Dietary Reference Intake reports, some nutrition education tools (e.g., the U.S. Food Guicle Pyramid and Canacia's Food Guicle to Healthy Eating) may require revision to remain current. The DRIs are one of several criteria that should be consiclereci when upciating such tools. Assuming that current nutrition education tools have been evalu- ateci to determine if they are consistent with the new reference intakes for nutrients, inclivicluals who wish to plan nutritionally acle- quate cliets for themselves can review their usual intakes with one of the food guides. Food labels can be used to help choose foods that will make up a healthful cliet. Inclivicluals can further plan their intakes to be consistent with clietary guidelines (e.g., Dietary G~'ide- lines for Americans tUSDA/HHS, 2000], Canada's Guidelines for Healthy Eating Health Canada, 1990a] ). Gaps or excesses identified can then be remeclieci by planning to alter the type or amount of 35

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36 DIETARY REFERENCE INTAKES foocis selected from the various food groups, by using fortified foocis, or if necessary, by using nutrient supplements. INTRODUCTION The Dietary Reference Intakes (DRIB) are used to establish goals in planning cliets for inclivicluals. This may include: (1) providing guidance to healthy inclivicluals who are concerned about meeting their nutrient neecis, (2) counseling those with special lifestyle considerations (e.g., athletes and vegetarians) or those requiring therapeutic cliets, (3) formulating cliets for research purposes, and (4) developing fooci-baseci clieta~y guidance for inclivicluals. This chapter focuses on planning cliets for normal healthy inclivicluals. Other situations, including planning therapeutic cliets, are aciciresseci in Chapter 6. Planning cliets for inclivicluals involves two steps. First, nutrient goals must be set that are appropriate, taking into account various factors that may have an impact upon nutrient neecis. Figure 2-1 provides an algorithm for this process. In this chapter the goal for incliviclual planning is to ensure that the cliet as eaten has an accept- ably low probability of nutrient inacloquacy while simultaneously minimizing the risk of nutrient excess. This goal is achieved with | Individual | Are there "special considerations"? No Plan so that the RDA or Al for age/sex is met Remain below the UL Other Tutrients Yes e.g., smoker (vitamin C) athlete (iron) vegetarian (iron, zinc) ill person (nutrients affected by illness) Plan for appropriate intakes of specific nutrients of concern based on special considerations FIGURE 2-1 Schematic decision tree for planning diets for individuals.

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USING DRIs IN PLANNING DIETS FOR INDIVIDUALS 37 cliets that meet the recommencleci intakes (Recommencleci Dietary Allowance or Acloquate Intake) without exceeding the Tolerable Upper Intake Level. Observed intakes may have a high probability of being inacloquate or excessive on any given clay, but a low proba- bility over time. When comparing observed intakes to nutrient goals, planners neeci to be conscious of the errors associated with brief assessments of clietary intake. It is very difficult to obtain accurate estimates of inclivicluals' usual nutrient intakes because intakes typically vary so much from one clay to the next. Dietary intakes assessed by multiple Manhour recalls, clietary records, or quantitative cliet histories provide the strongest bases for quantitative assessments of nutrient acloquacy, but no method is without error. A full discussion of the uncertainty associated with estimates of an incliviclual's usual intake cleriveci from these methods can be found in the DRI report on clietary assessment (IOM, 2000a). Food frequency questionnaires are not recommencleci for use in assessments of nutrient acloquacy because they have not been found to yield sufficiently accurate estimates of inclivicluals' usual intakes of specific nutrients. The second step in planning a cliet for an incliviclual is to develop a clietary plan that the incliviclual will consume. While the art of crafting appropriate clietary patterns and counseling inclivicluals to achieve them is beyond the scope of this report, information is pro- vicleci on how to use the DRIs to accomplish these tasks. SETTING APPROPRIATE NUTRIENT GOALS . . As explained in Chapter 1, Dietary Reference Intakes (DRIB) con- sist of four types of reference intakes that are used to assess and plan diets of individuals and groups: the Estimated Average Require- ment (EAR), the Recommencleci Dietary Allowance (RDA), the Acle- quate Intake (AI), and the Tolerable Upper Intake Level (UL). The EAR is not used as a goal in planning individual diets. By definition, a cliet planned to provide the EAR of a nutrient would have a 50 percent likelihood of not meeting an incliviclual's requirement, and this is an unacceptable degree of risk for the incliviclual. What follows is an examination of the RDA, AI, and UL as the three reference intakes related to planning diets for individuals. Recommended Dietary Allowance A major goal of clietary planning for inclivicluals is to achieve an acceptably low probability of nutrient inacloquacy for a given incli-

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38 DIETARY REFERENCE INTAKES victual. At the same time, the planner must consider whether increas- ing an incliviclual's intake beyond its customary level will result in any recognizable benefit. At low levels of intake, the probability of benefit associated with an increase in intake levels is high, but as intake levels rise above the EAR, the probability of benefit of an increased intake diminishes. Planning a cliet for an incliviclual that is likely to meet his or her requirement for a nutrient is complicated by the fact that the incliviclual's requirement is almost never known. Most inclivicluals have requirements close to the average require- ment for inclivicluals of their sex and age, and the best estimate of an incliviclual's requirement is thus the EAR. However, again by definition, half the inclivicluals in a group have requirements that exceed the EAR. Accordingly, an intake at the level of the EAR would be associated with an unacceptably high risk (50 percent) of not meeting an incliviclual's requirement and would not be suitable as a goal for planning. As intake increases above the EAR, the risk of inacloquacy decreases from 50 percent and reaches 2 to 3 per- cent at the RDA. Thus, the probability of inacloquacy is very low for inclivicluals with intakes at the RDA. However, the probability that a given incliviclual will benefit from an increase in intake also decreases to the same extent, and is near zero (less than 2 to 3 percent) when intake increases above the RDA. The new RDAs may be used as the targets for planning nutrient intakes that result in acceptably low probability of inacloquacy for the incliviclual. The RDA is intencleci to encompass the normal bio- logical variation in the nutrient requirements of inclivicluals. It is set at a level that meets or exceeds the actual nutrient requirements of 97 to 98 percent of individuals in a given life stage and gender group. This level of intake, at which there is a 2 to 3 percent proba- bility of the incliviclual not meeting his or her requirement, has traditionally been aclopteci as the appropriate reference when plan- ning for inclivicluals. It should be noted that selecting this intake level was, and continues to be, judgmental. When counseling an individual, it is important to consider whether any recognizable benefit will be achieved if the incliviclual's current intake level is increased. The likelihood of recognizable benefit must be weighed against the costs (monetary and otherwise) likely to be incurred in increasing this intake. An intake level could be chosen at which the risk to the incliviclual is either higher or lower than the 2 to 3 percent level of risk that is inherent in the definition of the RDA. When other levels are chosen they should be explicitly justified. For example, for a woman between the ages of 19 and 30 years, the . .

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USING DRIs IN PLANNING DIETS FOR INDIVIDUALS 39 RDA for iron is 18 ma, and is set to cover the neecis of women with the highest menstrual blood losses. A particular woman might feel that her menstrual losses were light. Accordingly, she may be willing to accept a 10 percent risk of not meeting her requirements, and thus would have as her goal consumption of only 13 mg of iron/clay (see Appendix I in the DRI micronutrient report tIOM, 20014~. Adequate Intake An AI is set when scientific evidence is not sufficient to establish an EAR and RDA. Uncler these circumstances the AI is the target that is used for planning incliviclual cliets. Although greater uncer- tainty exists in determining the probability of inacloquacy for a nutrient with an AI than for a nutrient with an RDA, the AI pro- vicles a useful basis for planning. However, the probability of inacle- quacy associated with a failure to achieve the AI is unknown. Unlike a nutrient with an EAR and an RDA, it is not possible to select a level of intake relative to the AI with a known probability of inacle- quacy. AIs are set in a variety of ways, as clescribeci elsewhere (i.e., IOM, 1997, 1998a, 2000b, 2001, 2002a). But in general they are the observed mean or meclian nutrient intakes by groups of presumably healthy inclivicluals, or they are baseci on a review of ciata cleriveci from both clietary and experimental approaches (e.g., the AIs for calcium and vitamin D tIOM, 1997] ~ . Regardless of how an AI was established, intake at the level of the AI is likely to meet or exceed an incliviclual's requirement, although the possibility that it could fail to meet the requirements of some inclivicluals cannot be clis- counteci. To11erab11e Upper Intake I~eve11 A UL also is provicleci for many nutrients. The UL is the highest level of chronic ciaily nutrient intake that is likely to pose no risk of adverse health effects to almost all inclivicluals in the specified life stage and gentler group. In general, intakes from food, supple- ments, and other sources (such as water) should be planned so that the UL is not exceeded. The UL is not a recommended level of intake, but an amount that can be tolerated biologically, with no apparent risk of adverse effects, by almost everyone. Risk to the individual is minimized by diets and practices that provide levels of nutrients below the UL, and thus when planning incliviclual cliets, the UL should not be exceeded.

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40 DIETARY REFERENCE INTAKES For most nutrients, intakes at or above the UL would rarely be attained from unfortified food alone. For example, the intake of a 31-year-olci woman who consumed 3.0 mg of vitamin B6 was at the 99th percentile of the intakes from food sources reported in the 1994-1996 Continuing Survey of Food Intakes by Inclivicluals (CSFII) in the United States (IOM, 1998a). Her RDA is 1.3 mg/ciay, and the UL is 100 mg/ciay. If this same woman clecreaseci her intake to 1.43 mg/ciay, it would be similar to the bOth percentile of intakes in the CSFII. In either case, her intake would be above the RDA and well below the UL. Even if she acicleci a serving of a highly fortified cereal that contained 2.0 mg of vitamin B6 per serving to her intake each clay, her usual intake would still be well below the UL. As reported in the CSFII, few inclivicluals haci intakes from foocis that exceecleci the UL. However, since these ciata were collected, fortification of foocis in the United States has increased. In acicli- tion, these ciata clici not capture supplement usage. Therefore, it is probable that current intake levels of vitamin B6 and other nutri- ents from food sources alone might be higher than those reported in the CSFII. Close attention to intake from highly concentrated sources of nutrients, such as highly fortified foocis or supplements (particularly high-close single nutrient supplements or high-potency multiple- nutrient supplements) may be warranted for some inclivicluals. For some nutrients, total intake may exceed the UL, especially if a per- son consumes large amounts from supplements and also has a high intake from food sources. For example, if the same 31-year-olci woman, in aciclition to her cliet (the 99th percentile of B6 intake of 3.0 mg/day), consumed a high-potency single supplement capsule of vitamin B6 that provicleci 80 mg/ciay, her total intake would be 83 mg/ciay. This amount greatly exceeds the RDA of 1.3 mg/ciay and approaches the UL of 100 mg/ciay. If she consumed two supple- ment capsules per clay, her intake would exceed the UL and she would be at potential risk of sensory neuropathy, the adverse effect used to set the UL for vitamin B6. Suppose that the same woman consumed a high-potency single supplement of zinc that provicleci 25 mg/ciay in aciclition to her ciaily clietary intake of 10 ma. Her total zinc intake would be 35 ma/ clay, which exceeds the RDA of 8 mg/ciay and approaches the UL of 40 mg/ciay. If she also consumed a fortified cereal with 100 percent of the Daily Value for zinc (15 mg), the UL would be exceecleci. Careful attention must be given when planning diets for individuals consuming high-close supplements or multiple sources of fortified foocis so that total intake floes not exceed the UL. There is no

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USING DRIs IN PLANNING DIETS FOR INDIVIDUALS 41 clocumenteci advantage to intakes that exceed the RDA or AI for healthy persons. PLANNING FOR ENERGY INTAKES OF INDIVIDUALS The underlying objective of planning for energy is similar to plan- ning for nutrients to attain an acceptably low risk of inacloquacy and of excess. The approach to planning for energy, however, clickers substantially from planning for other nutrients. When planning for inclivicluals for nutrients such as vitamins, minerals, and protein, one plans for a low probability of inacloquacy by meeting the Recom- mencleci Dietary Allowance (RDA) or Acloquate Intake (AI), and a low probability of excess by remaining below the Tolerable Upper Intake Level (UL). Even though intakes at or above the RDA or AI are almost certainly above an incliviclual's requirement, and thus would have little or no likelihood of benefit, there are no adverse effects to the incliviclual of consuming an intake above his or her requirement, provicleci intake remains below the UL. The situation for energy is quite different. The best way to assess and plan for energy intake of inclivicluals is to consider the health- fulness of their body weights (or body mass inclex tBMI] ~ because with energy there is an obvious adverse effect to inclivicluals who consume intakes above their requirements over time, weight gain occurs. This difference is reflected in the fact that there is no RDA for energy, as it would be inappropriate to recommenci an intake that exceecleci the requirement (anci would leaci to weight gain) of 97 to 98 percent of inclivicluals. Instead, equations have been clevel- opeci that reflect the total energy expenditure (TEE) as estimated from doubly labeled water ciata and associated with an incliviclual's sex, age, height, weight, and physical activity level. The product of these equations is termed an estimated energy requirement (EER) (IOM, 2002a). Although different equations were clevelopeci for normal-weight and overweight inclivicluals, because they are quite similar, it is rec- ommencleci that the equations for normal-weight inclivicluals be used for all inclivicluals (IOM, 2002a). All equations predict total energy expenditure and, by definition, the intake required to main- tain an individual's current weight and activity level. They were not clesigneci, for example, to leaci to weight loss in overweight inclivicluals. However, just as is the case with other nutrients, energy neecis vary from one incliviclual to another, even though their characteristics may be similar. This variability is reflected in the standard deviation (SD) of the requirement estimate, which allows for estimating the

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42 DIETARY REFERENCE INTAKES range within which the incliviclual's requirements could vary. Note that this floes not imply that an incliviclual would maintain energy balance at any intake within this range; it simply indicates how vari- able requirements could be among those with similar characteristics. For example, the equation for the EER (IOM, 2002a) for normal- weight women 19 to 50 years of age is: EER (kcal) = 354.1 - (6.91 x age ty1) + physical activity coefficient x (9.36 x weight ~kg] + 726 x height tm] ~ This equation can be applied to a 33-year-olci woman, 1.63 m in height and weighing 55 kg (BMI = 20.8 kg/m2), whose activity is equivalent to walking about 2 mi/ciay (this level of activity would be categorized as "low active," and the physical activity coefficient for this activity level is 1.12~. Her estimated energy requirement would be calculated as: EER (kcal) = 354.1 - (6.91 x 33) + 1.12 x (9.36 x 55 + 726 x 1.63) = 2,028 This value of 2,028 kcal represents the average energy require- ment of women with her specified characteristics (age, height, weight, and activity level). The SD of the EER is estimated as 70 percent of the stanciarci error of the fit of the regression equation (IOM, 2002a). In this example, the SD of the EER would be 160 kcal. The range within which a given woman's energy requirement likely falls (e.g., the 95 percent confidence interval) would be 2,028 + (2 x 160 kcal), or between 1,708 and 2,348 kcal/day. It should be emphasized that usual energy intakes are highly cor- relateci with energy expenditure. This means that most people who have access to enough food will consume an amount of energy very close to what they expend, and as a result, maintain their weight within relatively narrow limits over reasonable periods of time. Any changes in weight that do occur usually reflect small imbalances in intake over expenditure accumulated over a long period of time. For normal inclivicluals who are weight-stable, at a healthy weight, and performing at least the minimal recommencleci amount of total activity, their energy expenditure (anci recommencleci intake) is their usual energy intake. This also applies to maintaining current weight and activity level in overweight individuals. Thus, if one knew an incliviclual's usual energy intake, one would plan to maintain it rather than calculate the EER to obtain an estimate. In most situa- c,

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USING DRIs IN PLANNING DIETS FOR INDIVIDUALS 43 lions, however, the usual energy intakes of inclivicluals are not known, so the equations for TEE are useful planning tools. Using the Estimated Energy Requirement to Maintain Body Weight in an Individual When the planning goal is to maintain body weight in an inclivici- ual with specified characteristics (age, height, weight, and activity level), an initial planning estimate for energy intake is provicleci by the equation for TEE of an incliviclual with those characteristics. By definition the estimate would be expected to underestimate the true energy expenditure 50 percent of the time, and to overestimate it 50 percent of the time, leacling to corresponding changes in body weight. This indicates that monitoring body weight would be required when using the equations to estimate incliviclual energy expenditure. For example, if one was enrolling subjects in a study in which it was important to maintain body weight with a specified activity level, one might begin by fouling each incliviclual the amount of energy estimated using the equation for their EER. Body weight would be closely monitored over time, and the amount of energy provicleci to each incliviclual would be acljusteci up or clown from the EER as required to maintain body weight. Planning for Macronutr~ent Distribution In addition to planning a diet that meets an individual's energy requirements and has a low probability of nutrient inacloquacy and potential risk of excess, an individual's intake of macronutrients (e.g., carbohydrate, fat, and protein) should be planned so that carbohydrate, total fat, n-6 and n-3 polyunsaturated fatty acids, and protein are within their respective acceptable ranges (IOM, 2002a). For example, consider the 33-year-olci, low-active woman cliscusseci previously, who had an EER of approximately 2,000 kcal. The ranges within which her macronutrient intakes should fall are shown in Table 2-1. DEVELOPING DIETARY PLANS Once appropriate nutrient intake goals have been iclentifieci for the incliviclual, these must be translated into a clietary plan that is acceptable to the incliviclual. This is most frequently accomplished using nutrient-baseci food guidance systems.

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44 DIETARY REFERENCE INTAKES TABLE 2-1 Distribution of Macronutrient Intake Using the Acceptable Macronutrient Distribution Range for a 33-Year- Olci, Low-Active Woman Acceptable Range of Macronutrient Macronutrient Intake for Energy Distribution Range Requirement of Macronutrient ( % of energy) a ~2000 kcal (g) Carbohydrate 45-65 225-325 Protein 10-35 50-175 Total fat 20-35 44-78 n-6 Polyunsaturated fatty acids 5-10 11-22 n-3 Polyunsaturated fatty acids 0.6-1.2 1.3-2.7 Added sugars < 25 < 500 kcal a Source: IOM (2002a). Nutr~ent-Based Food Guidance Systems in the United States and Canada Dietary reference stanciarcis (e.g., the former Recommencleci Dietary Allowances tRDAs] in the United States and the Recommencleci Nutrient Intakes tRNIs] in Canacia) have been used to provide fooci- baseci clietary guidance in many ways, including through clevelop- ment of national food guides and clietary guidelines for healthy populations and as a basis for information on food and supplement labels. Dietary guidance systems and food composition tables are the most universally accessible sources of nutrition information available to practitioners and laypersons. Practitioners may also use many other sources of nutrition information for incliviclual plan- ning (such as new information in the scientific literature or infor- mation on disease prevention from professional associations). In practice, guidance about food choices, such as the U.S. Food Guide Pyramid or Canada's Food Guide to Healthy Eating, are widely used. These guides recommenci that users select the appro- priate amount of food for their age, sex, physiological status, body size, and physical activity level from among a range of servings from several different food groups. The intent is that over a period of clays to weeks, varied choices within each group allow recommencleci intakes of nutrients to be attained. The former RDAs and RNIs were two of the major elements from which these food guidance systems were clevelopeci; future revisions will uncloubtecily consider the new Dietary Reference Intakes (DRIs). Thus, reference stanciarcis for

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USING DRIs IN PLANNING DIETS FOR INDIVIDUALS 45 nutrients are implicitly used in planning incliviclual cliets when food guides are used. The following sections present a brief summary of the ways that nutrient recommendations have been used in food guides and food labels. Appendix B provides a more cletaileci description. Food Guides in the United States and Canada Both the Food Guide Pyramid (Figure 2-2) and the Food Guide to Healthy Eating (Figure 2-3) are guides for healthy persons to achieve acloquate total nutrient intakes from food sources. Acljust- ments in intakes clue to varying requirements (e.g., age, sex, physio- logical status) are accomplished with these tools by mollifying the number of servings consumed. In these systems, foocis within a group are assumed to have particular and fairly similar nutrient profiles, and the specified serving sizes are baseci in part on an amount that would provide comparable levels of key nutrients from Fats, Oils, & Sweets USE SPARINGLY Milk, Yogurt, & Cheese Group 2-3 SERVINGS Vegetable Group 3-5 SERVINGS FIGURE 2-2 U.S. Food Guide Pyramid. SOURCE: USDA (1992~. Meat, Poultry, Fish, Dry Beans, Eggs, & Nuts Group 2-3 SERVINGS Fruit Group 2-4 SERVINGS Bread, Cereal, Ring ~ Pacts Group 6-11

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46 DIETARY REFERENCE INTAKES ~ Health Sante ~ ~ Canada Canada ~ ~ {Ed _ ~ TO HEALTHY EATING FOR PEOPLE FOUR YEARS AND OVER Enjoy a variety Of foods from each OrouD every dav Choose ioweF fat foods more often. Hot Cereal 175 mL 3/4 cup 1 Bagel, Pita or Bun Pasta or Rirn 250 mL 1 cup 1 Serving Fresh, Fmzen or Canned Vegetables or Fruit 125 mL 1 Medium Size Vegetable or Fruit 1/2 cup rig 3'X1"x155 2 Slices 50q 50g Beans 19R pan ml 113-213 Can 50-100 g Meat, Poultry or Fish 50-100 g 1-2 Eggs 100g 1/3 cup FIGURE 2-3 Canada's Food Guide to Healthy Eating. SOURCE: Health Canada ( 1991~ . Other Foods Taste and enjoy- ment can also come from other foods and bever- ages that are not part of the 4 food groups. Some of these foods are higher in fat or Calories, so use these foods in moderation.

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USING DRIs IN PLANNING DIETS FOR INDIVIDUALS 47 foocis within the group. For example, each serving in the "meat and alternatives" group is a good source of protein. One serving of any of the alternatives in this group would have approximately the same amount of protein. As inclicateci earlier, the design of food guidance systems is that, over a period of time (clays or weeks), inclivicluals who consume the recommencleci number of servings from each food group, and who choose a variety of foocis within each group, will obtain the recommencleci intakes for all nutrients. As an example, consider an active 22-year-olci pregnant woman who receives clietary counseling. Using the Food Guide Pyramid as a guide to achieve the recommencleci intakes of nutrients, her meal pattern would include a minimum of three servings (7 oz) of protein-rich foocis, three servings of dairy products, two servings of fruits, and three servings of vegetables (focusing on foocis rich in folate, vitamin C, and ,3-carotene), and seven servings from the breaci, cereal, rice, and pasta group. Aciclitional servings of foocis from these groups and from the tip of the pyramid would be acicleci if neecleci to meet energy requirements. From this the nutritionist would develop a menu plan and an example of food choices baseci on the above clietary pattern. Table 2-2 is an example of planning a clay's menu using the Food Guide Pyramid. Table 2-3 compares its nutrient content to the cur- rent RDAs or Acloquate Intakes (AIs) for nutrients. It can be seen that the sample clay's menu exceeds intake recommendations for all nutrients, even though it is for only one clay. It is important to emphasize that food choices within this menu pattern would vary, and the intake from the one sample clay will not accurately reflect the average intake over several clays. For example, the average intake of nutrients provicleci by the sample clay's menu in amounts sub- stantially above the RDA could decrease (e.g., the sample menu provides vitamin A in amounts well above the RDA because carrots, a concentrated source of the provitamin A carotenoici, ,3-carotene, were inclucleci). It is expected that varied food choices within the menu pattern would allow average intake to meet recommencia- tions for most nutrients and energy neecis. Those who use food guides to plan menus for inclivicluals must recognize that when new reference intakes for nutrients are devel- opeci, there is an unavoidable time lag before the guides can be assessed to determine whether they support the new nutrient refer- ence stanciarcis. When new reference intakes have changed consici- erably from previous standards, a food guide may not be appropri- ate. For example, the new RDAs for vitamin A (IOM, 2001), while somewhat lower than the previous stanciarcis, specify the use of

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48 DIETARY REFERENCE INTAKES TABLE 2-2 Sample Planning Menu for a Prenatal Client Aged 22 Years Baseci on the Food Guicle Pyramid Mid-Afternoon Breakfast Lunch Snack Dinner Evening Snack 3/4 cup 2 oz tuna fish 5 wheat 1 cup skim 1 cup yogurt orange juice (PRO) crackers milk (DG) (nonfat) (FG) 1 tsp (BCG) 4 oz roasted (DG) 1 cup fortified mayonnaise 2 tbsp peanut chicken 1/2 cup fresh wheat cereal (FSG) butter breast blueberries with raisins 2 slices whole (PRO) (PRO) (FG) (BCG) wheat bread 1 apple (FG) 1 cup cooked 1/4 cup dry 1 slice mixed (BCG) (with 1 cup skim long grain roasted grain toast lettuce and milk (DG) rice (BCG) almonds (BCG) tomato) 1/2 cup (PRO) 1 tsp 1/2 cup cooked margarine cooked spinach (FSG) carrots (VG) 1 tbsp jelly (VG) 1 cup tossed (FSG) 1 glass salad (VG) 1 cup skim sweetened 2 tbsp low-fat milk (DG) iced tea French dressing (FSG) NOTE: Nutrient analysis was performed using Nutritionist Five, First DataBank, Inc. 2000. FG = fruit group, BCG = bread and cereal group (bread, cereal, rice, and pasta), FSG = fat and sweet group (fats, oils, and sweets), DG = dairy group (milk, yogurt, and cheese), PRO= protein-rich group (meat, poultry, fish, dry beans, eggs, nuts), VG = vegetable group. retinal activity equivalents (RAE) rather than retinal equivalents (RE) when calculating or reporting the amount of total vitamin A in mixed or plant foocis. An RAE gives the ,3-carotene:retinol equiv- alency ratio as 12:1, versus the former equivalency of 6:1 (NRC, 1989~. The increased ratio means that a larger amount of ,3-carotene is neecleci to meet the vitamin A requirement for inclivicluals who rely on plant sources of this vitamin in their cliet. Therefore, newer food guides may neeci to reflect an increase in the amount of darkly colored, carotene-rich fruits and vegetables needed to provide vita- min A in the cliet. Consideration should be given to the new DRIs when food guides are upciateci. In the interim, dietetic practitioners who plan cliets should familiarize themselves with the nutrient intake recommen-

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USING DRIs IN PLANNING DIETS FOR INDIVIDUALS 49 TABLE 2-3 Comparison of Nutrient Intake with Current Recommencleci Intake, Baseci on a Sample Planning Menu (Table 2-2) Planned RDA or AI Planned Intake as Nutrient Intake for Pregnancya % of RDA or AI Energy (kcal) 2,363 2,365 EERb Protein (g) 131 71 c 185 Carbohydrate (g) 320 175 183 Vitamin A (,ug RAE)d 2,253 770 ,ug RAE 293 Vitamin C (mg) 140 85 165 Vitamin E (ma oc-tocopherol)e 15 15 100 Thiamin (mg) 1.9 1.4 135 Riboflavin (mg) 3.5 1.4 250 Niacin (mg) 44 18 244 Vitamin B6 (mg) 3.0 1.9 158 Folate (,ug) 606 600 ,ug DFEf 101 Vitamin B12 (pa) 8.2 2.6 315 Calcium (mg) 1,841 1,000 184 Copper (mg) 1.9 1.0 190 Iron (mg) 41 27 152 Magnesium (mg) 649 350 185 Phosphorus (mg) 2,505 700 358 Zinc (mg) 14 11 127 a RDA = Recommended Dietary Allowance, AI = Adequate Intake. b Estimated Energy Requirement (EER) = 354.1 - (6.91 x 22) + 1.27 x (9.36 x 54 + 726 x 1.65) + 0 (pregnancy energy deposition for first trimester) = 2,365 kcal. c Protein = 46 g/day + 25 g/day of additional protein during pregnancy. d Database values for vitamin A in retinal equivalents (RE) were converted to retinal activity equivalents (RAE). For retinal, 1 RE = 1 RAE. For carotenoids, 1 RE = 0.5 RAE. e Nineteen oc-tocopherol equivalents (oc-TE) x 0.8 mg = 15.2 mg oc-tocopherol, where 0.8 is the ratio of oc-tocopherol to oc-TE. f 1 ,ug dietary folate equivalent (DFE) = 1 ,ug food folate. cations that have changed substantially, examine existing tools, and mollify methods as necessary to ensure that these targets are met. For tif ed Foods Fortified and enriched foocis have the advantage of providing aciclitional sources of certain nutrients that might otherwise be present only in low amounts in some food sources. Therefore, they are helpful in planning diets to reduce the probability of inadequacy of specific nutrients. In addition, they may afford the opportunity

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so DIETARY REFERENCE INTAKES to acici nutrients in highly bioavailable forms, as is the case with folate- and vitamin B~2-fortifieci foocis. The fortification of foocis is undertaken for public health reasons. For example, in the United States and Canada, ioclizeci salt; cereal grains fortified with thiamin, riboflavin, niacin, iron, and folate; and vitamin D-fortifieci milk were intencleci to recluce the risk of inacloquate intakes of those nutrients. Fortification provides a fooci- baseci means for increasing intakes of particular nutrients and in some cases can be especially targeted to specific groups at risk of shortfalls in specific nutrients (e.g., infant formulas and infant cereals fortified with iron are useful to meet the high iron neecis of older infants and young children. In aciclition to fortification initiated by government authorities for public health reasons, inclepenclent voluntary fortification uncler- taken by private industry is also allowoci in the United States. Often the amount of a nutrient acicleci cluring such voluntary fortification may be baseci on commercial appeal, rather than public health analysis of desirable clietary aciclitions. It is necessary to use highly fortified foocis selectively when planning cliets so that they contrib- ute to nutrient acloquacy without causing excess intakes. Canaclian regulations are different and do not permit independent voluntary fortification. (For aciclitional information, see Appendix D.) Nutrient Supplements Nutrient supplements provide an aciclitional means of consuming specific nutrients that otherwise might be in short supply. Depenci- ing on their formulation, they may consist of single nutrients or a combination of many different vitamins, elements, or other nutri- ent and nonnutrient ingredients. Doses vary from levels close to the RDA or AI to several times these levels. Supplements are useful when they fill a specific identified nutrient gap that cannot or is not otherwise being met by the individual's food-based dietary intake. For example, it is recommencleci that women who might become pregnant obtain 400 ,ug of folic acid from the use of fortified foocis or supplements, in addition to obtaining folate from a varied diet. For pregnant women, iron supplements may be suggested to meet needs for this nutrient that are unlikely to be achieved from food sources alone (IOM, 1992~. However, there can be clisacivantages associated with supplement use. For example, inclivicluals at risk may not adhere to the supplement regimen. In other cases, those who are already consuming the RDA or AI for most nutrients from food sources may use supplements, but they will not achieve any

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USING DRIs IN PLANNING DIETS FOR INDIVIDUALS 51 recognized health benefit from consuming more of these nutrients as supplements and may be at risk of excessive intake. Food and Supplement Labels in the United States and Canada In the United States, the percent of Daily Values stated on food and supplement labels for vitamins and elements is baseci on the Reference Daily Intakes (RDI) established by the Food and Drug Administration. In the early l990s, the term RDI replaced the term "US RDA" for vitamins and elements on food labeling. The current RDI values are the same as the US RDAs that were provicleci on food labels in the past, which are baseci on the highest RDA across the various age and gentler categories (with the exception of pregnancy and lactation) from the 1968 RDAs (NRC, 1968~. Aciclitional RDI values have been acicleci for nutrients for which there were no RDAs in 1968 (e.g., folate). Table 2-4 compares the current RDA or AI to the US RDI. An example of a U.S. food label is shown in Figure 2-4. In Canada the food and supplement labels are baseci on the high- est RNI for any age and gentler group over age 2 from the 1983 Canaclian RNIs (Consumer and Corporate Affairs Canada, 1988~. Table 2-4 also compares the values used for the food label in Canada with the current RDAs or AIs. Canaclian nutrition labeling has recently been revised, and the new label closely resembles the U.S nutrition label. An example of the new Canaclian label format is shown in Figure 2-~. Similar to the previously cliscusseci situation with food guides, food labels also may not reflect the most current nutrient reference stan- ciarcis. Consumers neeci to be aware of the discrepancies that exist when using the food label information to plan their cliets. Dietary Guidelines in the United States and Canada The U.S. Dietary Guidelines and Canacia's Guidelines for Healthy Eating are designed to provide advice about dietary patterns that promote health and prevent chronic disease in a healthy popula- tion (see Appendix B). The clietary guidelines describe food choices that will help inclivicluals meet their recommencleci intake of nutri- ents. Like the DRIB, the guidelines apply to cliets consumed over several days not a single day or single meal. Nutrient reference stanciarcis are not the primary focus of clietary guidelines, but when selecting healthy food choices baseci on the guidelines, inclivicluals are more likely to meet recommencleci intakes of nutrients and to have macronutrient intakes that fall within the acceptable macro-

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~2 DIETARY REFERENCE INTAKES TABLE 2-4 Comparison of the Recommencleci Dietary Allowances (RDA) and Acloquate Intakes (AI) with Daily Values (DV) for Vitamins and Minerals Used on Food Labels in the United States and Canada U.S. Reference Daily Intake Nutrient RDA or AIa (Dv)b Canadian DVC Vitamin A (,ug) Vitamin C (mg) Vitamin D (,ug) Vitamin E (ma oc-tocopherol) Thiamin (mg) Riboflavin (mg) Niacin (mg) Vitamin B6 (mg) Folate (,ug) Vitamin B12 (pa) Pantothenic acid (mg) 5 Biotin (,ug) Choline (mg) Calcium (mg) Chromium (,ug) Copper (mg) Fluoride (mg) 900 RAE 90 15 15 1.2 1.3 16 1.7 400 2.4 30 550 1,300 35 0.9 4 5,000 IU 60 10 30 IU 1.5 1.7 20 2.0 400 10 300 1,000 RE 60 5 10 1.3 1.6 23 NE 1.8 220 2 7 1,000 1,100 120 Iodine (,ug) 150 150 160 Iron (mg) 18 18 14 Magnesium (mg) 420 400 250 Phosphorus (mg) 1,250 1,000 1,100 Selenium (,ug) 55 Zinc (mg) 11 15 9 a Highest values for any age/sex category except pregnant/lactating. RAE = retinal activity equivalents. b The U.S. DVs are higher than the recently recommended intakes (RDAs or AIs) for thiamin, riboflavin, niacin, vitamin Be, vitamin B12, pantothenic acid, biotin, chromium, copper, and zinc. The DVs are lower for vitamin C, vitamin D, calcium, magnesium, and phosphorus. It is not possible to directly compare vitamin A, vitamin E, and folate because the DV is in International Units (IU) while the RDA is in mg or ,ug and differ- ent bioavailability factors are incorporated into the values. There are three nutrients with an RDA or AI but no DV (choline, fluoride, and selenium). c The Canadian DVs are higher than the RDAs or AIs for thiamin, riboflavin, niacin, vitamin Be, pantothenic acid, and iodine. The DVs are lower for vitamin C, vitamin D, vitamin E, folate, vitamin B12, calcium, iron, magnesium, and phosphorus. There are six nutrients with an RDA or AI but no RDI (biotin, choline, chromium, copper, fluo- ride, and selenium). RE = retinal equivalents, NE = niacin equivalents.

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USING DRIs IN PLANNING DIETS FOR INDIVIDUALS 53 Sugars 59 C)alories from Fat 11 Your Daily Values may be higher or lower depending on your calorie needs: Calories: Total Fat Less than Sat Fat Less than Cholesterol Less than Sodium Less than Total Carbohydrate FIGURE 2-4 U.S. food label. SOURCE: FDA (2000~. 65g 20g 300mg 2,500 nutrient distribution ranges. For example, the U.S. guideline "Let the Pyramid Guide Your Food Choices" promotes dietary nutrient acloquacy. The Canaclian guideline "Enjoy a Variety of Foods" is baseci on the principle that foocis contain combinations of nutrients and other substances that are neecleci for good health. Thus, an incliviclual is more likely to meet nutrient neecis by eating a variety of foocis. The U.S. guidelines also emphasize choosing a variety of grains, especially whole grains, and consuming adequate servings of fruits and vegetables, which provide important nutrients that may be low among some population subgroups (e.g., pregnant women

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~4 FIGURE 2-5 Canadian food label. SOURCE: Health Canada (2002~. DIETARY REFERENCE INTAKES 716~ and the elclerly). The guidelines state that fruits and vegetables are excellent sources of folate and antioxidant nutrients such as vita- min C, vitamin E, and carotenoicis, and thus help to prevent nutri- ent inacloquacy. In aciclition, high intakes of fruits and vegetables are associated with recluceci disease risk and are good sources of phytochemicals. The guidelines also serve to promote the impor- tance of moderation and avoiding excess salt, fat, sugar, and alco- holic beverages. The guidelines, if followoci, also ensure moclera- tion in intakes of foocis that provicle energy but few nutrients.