Dietary Reference Intakes: development and uses for assessment of micronutrient status of women--a global perspective

This paper reviews the process of developing the Dietary Reference Intakes (DRIs) and provides a synopsis of the micronutrient status of women worldwide. At a 1993 symposium held by the Food and Nutrition Board (FNB) of the Institute of Medicine (IOM), it was decided that the Recommended Dietary Allowances (RDAs) would be replaced by the DRIs, which would address several issues that the RDAs did not, including chronic disease risk reduction, upper levels for nutrients where toxicity data existed, and the possible health benefits of some food components that did not meet the traditional definition of a nutrient. Another important distinction is that because the DRIs are comprised of 4 reference values -the Estimated Average Requirement (EAR), RDA, Adequate Intake (AI), and a tolerable Upper Level (UL) -and not a single reference value like the previous RDAs, they could be used to differentiate planning from diagnosis or assessment. The latest DRIs and nutrient intakes are shown for iron, zinc, calcium, Vitamin A and folate status in women in the United States. Data on the micronutrient status of women globally are much more limited. Summary statistics on iron deficiency anemia, night blindness, and risk of zinc deficiency are summarized.     

Challenges in using the dietary reference intakes to plan diets for groups

A recent report describes a new paradigm for planning the dietary intakes of groups, the goals of which are to achieve low prevalences of both inadequate and excessive intakes. However, there are many challenges involved in properly implementing these methods, and pilot studies are urgently needed. For individuals, the target for nutrient intakes is usually the Recommended Dietary Allowance (RDA); for nutrients without an RDA, the Adequate Intake (AI) can be used. Intakes should be planned so they do not exceed the Tolerable Upper Intake Level (UL). Several applications illustrating how to use the DRIs for planning the diets of individuals have been published, so this review will focus primarily on the methods that are recommended for planning the diets of groups.     

Using DRIs as the basis for dietary guidelines

Dietary Reference Intakes (DRIs) are nutrient standards that may be used to plan nutrient intakes. Thus, they are useful as the basis for formulating dietary guidelines. The guidelines are often presented to the public as a food guide that will promote nutrient adequacy without risk of excessive intake. Such guides typically use the Recommended Dietary Allowances (RDAs) as intake targets because intake at the RDA is associated with a high probability of nutrient adequacy for healthy persons. During the development of the MyPyramid food guide for the United States, several questions were addressed: (1) What energy levels will be covered by the specific food patterns within the food guide? Each pattern should promote nutrient adequacy for the targeted energy intake level, which may include different age and gender groups. (2) What nutrients will be targeted by the food patterns? They should promote nutrient adequacy while also ensuring that intakes are not excessive for food components such as sodium, saturated fat, and cholesterol. (3) What food groups will be included in the food patterns, and how will their nutrient profiles be determined? After these decisions have been made, then the recommended amounts of each food group can be determined. A unique approach has been used to develop Canada's Food Guide, which included a simulation of the effect of differing food choices within each food group. Dietary guidelines and food guides which are based on the DRIs have the potential to improve nutrient intakes for consumers who follow them.     

Recommended Dietary Allowances should be used to set Daily Values for nutrition labeling

Guiding principles were recently suggested for revising the Daily Values (DVs) used for nutrition labels on foods and dietary supplements. These principles incorporate the new Dietary Reference Intakes, which are nutrient standards issued between 1997 and 2005 by the Institute of Medicine. Most of the principles are likely to lead to a more accurate basis for the DVs. However, the recommendation to use the Estimated Average Requirement (EAR) rather than the Recommended Dietary Allowance (RDA) should be reconsidered. Traditional public health messages to American and Canadian consumers have focused on nutrient intake levels with a high probability of being adequate. The RDA, with a 98% probability of adequacy, is designed to be the target nutrient intake for individuals; in contrast, the EAR has only a 50% probability of adequacy. Three considerations should lead to a preference for using the RDA rather than the EAR for the DVs: 1) consumers are likely to expect that a product (or a diet) with 100% of the DV has a high probability of nutrient adequacy; 2) use of the RDA for the DV will be consistent with other types of dietary guidance, such as the Dietary Guidelines for Americans 2005 and US food guides; and 3) use of the RDA as a standard for nutrient intake, rather than the EAR, has a potential benefit (a higher prevalence of adequate intakes) that exceeds potential risk (a higher prevalence of excessive intakes).     

The Status of Dietary Energy and Nutrients Intakes among Chinese Elderly Aged 80 and Above: Data from the CACDNS 2015

This study analyzed the status of dietary energy and nutrients intakes among the oldest-old in China. Data was obtained from the China Adult Chronic Disease and Nutrition Surveillance in 2015 (CACDNS 2015). We enrolled 1929 Chinese elderly people aged 80 and above who participated in both 3-day 24-h dietary recalls and household condiments weighing. The dietary intakes were calculated based on Chinese Food Composition Tables and assessed using Chinese Dietary Reference Intakes (DRIs). The dietary intakes of energy and most nutrients were all below the EAR or AI, except for fat, vitamin E, niacin, iron and sodium. As a result, daily dietary intakes of energy and most nutrients were inadequate in the oldest-old in China, especially vitamin A, vitamin B₁, vitamin B₂, folate and calcium, with the prevalence of deficiency more than 90%. Furthermore, the prevalence of inadequacy of vitamin C, zinc, selenium and magnesium was also high with the proportion below the EAR more than 60%. Approximately 30% of the subjects with dietary vitamin E intake did not reach AI, and more than 90% of subjects have reached AI in the intake of sodium, while more than 90% did not reach AI in potassium. The mean intakes of niacin and iron have reached EAR, but around 15% were still faced with the risk of deficiency. In addition, although the dietary energy intake was below EER, the energy contribution from fat in total population and all subgroups (region, age, gender, education level, material status, household income level groups) all exceeded the recommended proportion of 30% from the DRIs and close to or over 35%, is a significant concern. For the majority of nutrients, higher daily dietary intakes and lower prevalence of deficiencies were found in the oldest-old living in urban areas, aged 80–84 years, with high school and above education level, living with spouse and from high household income family. These findings indicates that the dietary intakes of energy and nutrients were inadequate, while the energy contribution from fat and dietary sodium intake were too high among the oldest-old in China. Most oldest-old were at high risk of nutritional deficiency, particularly for those who living in rural areas, with lower education level and from low household income.     

Dietary Reference Intakes (DRIs) in Japan

Following the comprehensive systematic review of domestic and overseas scientific evidence, the "Dietary Reference Intakes for Japanese, 2005 (DRI-J)" was published in April, 2005. The DRIs-J were prepared for health individuals and groups and designed to present a reference for intake values of energy and 34 nutrients to maintain and promote health and to prevent lifestyle-related diseases and illness due to excessive consumption of either energy or nutrients. The DRI-J also includes a special chapter for basic knowledge of DRIs. The energy recommendation is provided as an estimated energy requirement (EER), while five indices were used for nutrients: Estimated average requirement (EAR), recommended dietary allowance (RDA), adequate intake (AI), tolerable upper intake level (UL), and tentative dietary goal for preventing lifestyle-related [chronic non-communicable] diseases (DG). Whilst the first four indices are same as the ones used in other countries, DG is unique index in Japan, which was set as a reference value for preventing non-communicable diseases such as cardiovascular (including hypertension), major types of cancer and osteoporosis. This report (DRI-J) is the first dietary guidance in Japan, which applied evidence-based approach utilizing a systematic review process. Only a few articles from within Japan and other Asian countries could be used for its establishment. The project to establish the DRI-J revealed a severe lack of researchers and publications focused upon establishing DRIs for Japanese. Further review is therefore required in preparation for the next revision scheduled in 2010.     

Dietary Reference Intakes for Koreans (KDRIs)

For more than 40 years, Recommended Dietary Allowances for Koreans (KRDA) were used as references for nutrient intake. In 2002, the Korean Nutrition Society organized a committee to revise the KRDA, which were transformed into the new Dietary Reference Intakes for Koreans (KDRIs) in 2005. KDRIs include Estimated Average Requirements (EAR), Recommended Intake (RI), Adequate Intake (AI) and Tolerable Upper Intake Level (UL) for protein, essential amino acids and micronutrients, Estimated Energy Requirement (EER) for energy and Acceptable Macronutrients Distribution Ranges (AMDR) for macronutrients. Evidence-based methods were used to determine the reference value (s) and the levels of nutrient intake for each nutrient. The KDRIs expanded significantly the number of nutrients and the basic concepts of nutrient recommendations compared to the previously used KRDA. In addition, a new food guide, depicted as Food Tower for Koreans, was developed and appended to the KDRIs publication. Continued efforts are needed to facilitate the application of KDRIs as well as to improve the understanding of the concepts. Additional modifications will be made as more scientific data become available.     

Changes in Dietary Guidance: Implications for Food and Nutrient Databases

Two types of dietary guidance for Americans have recently been released, and both have important implications for the way data are organized on food and nutrient databases. New dietary reference intakes (DRIs) have been set for 17 nutrients, and in several cases the units for these recommendations do not match those traditionally carried on nutrient databases. Furthermore, some of the tolerable upper intake levels (ULs) are specified only for supplemental and fortification forms of nutrients, which necessitates calculating separate intake values for nutrients from foods and nutrients that are added to foods or taken as supplements. The year 2000 revision of the Dietary Guidelines for Americans also suggest new ways to evaluate dietary intakes: there is an increased emphasis on obtaining an appropriate number of servings from food groups such as fruits, vegetables, whole grains, and lowfat dairy products. To allow users of nutrient databases to provide relevant evaluations of dietary data, developers will need to consider carrying a much larger array of variables in order to calculate intakes of folate in folate equivalents, vitamin E as alpha-tocopherol (not as alpha-tocopherol equivalents), nutrients occurring in foods versus added or supplemental nutrients, and the number of servings from a variety of food groups.

• •For more information on the DRIs, see:.
• •For more information on the year 2000 Dietary Guidelines, see:

     

Longitudinal assessment of micronutrient intake among African-American and white girls: The National Heart, Lung, and Blood Institute Growth and Health Study

OBJECTIVE: Low intakes of micronutrients among adolescents may be linked to long-term health risks, especially in African-American girls. This report describes intake of key micronutrients relative to the Dietary Reference Intakes in a sample of African-American and white girls. DESIGN: Longitudinal analyses used data from 3-day food records collected in the National Heart, Lung, and Blood Institute Growth and Health Study. SUBJECTS/SETTING: Subjects included 1,166 white and 1,213 African-American girls (aged 9 to 18 years). MAIN OUTCOME MEASURES: Estimated usual daily intakes of vitamins A, E, C, D, B-6, B-12, magnesium, folate, calcium, and zinc were compared to the Adequate Intake (for vitamin D and calcium) or the Estimated Average Requirement (EAR) (all other micronutrients). STATISTICAL ANALYSES PERFORMED: Usual daily intake of each micronutrient was estimated. For nutrients with an EAR, the EAR cut-point method was used to assess the prevalence of low nutrient intakes. Mixed models were used to identify age and racial differences in usual daily intake of each nutrient. RESULTS: African-American girls consumed less vitamin A and D, calcium, and magnesium compared to white girls. Regardless of race, a substantial percentage of girls had intakes below the EAR: vitamin E (81.2% to 99.0%), magnesium (24.0% to 94.5%), folate (46.0% to 87.3%). Intakes of vitamins A, D, and C; calcium; and magnesium decreased across years. As girls aged, there was an increasing proportion with intakes below the EAR for vitamins A, C, B-6, and B-12. CONCLUSIONS: Food and nutrition professionals should continue to educate adolescent girls, especially those who are African American, about the importance of a nutrient-dense diet for optimum health.     

四川农村贫困地区儿童膳食营养状况评价

目的了解四川农村儿童膳食营养状况,为农村儿童营养干预提供依据。方法随机抽取四川省某县3个乡514名3～10岁农村儿童为研究对象,采用24h膳食回顾法和食物频率法进行膳食调查,并以中国居民膳食营养素参考摄入量（DRIs）为标准,评价膳食能量和各营养素摄入状况。结果调查对象膳食以粮谷类、蔬菜水果类为主;能量达到80%RNI者占18.5%,碳水化合物、脂肪和蛋白质的供能比分别为67.2%,20.4%和12.4%;蛋白质达到80%RNI者占11.7%,钙和铁摄入量达到80%AI值者分别为0.9%和36.2%。锌和视黄醇摄入量达到EAR值的儿童分别为12.4%和17.9%,铁和视黄醇均主要来源于植物性食物。结论四川农村儿童膳食结构不合理,能量和各种营养素摄入普遍不足。     

Interpreting and using the dietary references intakes in dietary assessment of individuals and groups

For individuals, a statistical approach is available to compare observed intakes to the EAR or AI (to assess adequacy), and the UL (to assess risk of excess). A more qualitative assessment of intakes involves comparison directly to the RDA to evaluate adequacy, but this is accurate only if long-term usual intake is known. For groups of people, the prevalence of inadequacy can usually be estimated as the proportion with intakes below the EAR, while the prevalence of potentially excessive intakes is estimated as the proportion above the UL. The accuracy of all assessments depends on unbiased and accurate intake estimates as well as a consideration of the effects of day-to-day variation in intake. Nutrition practitioners will find the new DRIs useful for assessing diets in a variety of settings. Computerized assessment systems will be important tools when incorporating these theoretical concepts into dietetic practice.     

Supplement use: is there any nutritional benefit?

OBJECTIVE: To examine the role of dietary supplements in improving total nutrient intakes in adults. DESIGN: Dietitian-administered 24-hour recalls (of intake including supplements) were conducted in 1997 and 1998. Supplement users were categorized into groups based on the types of supplements used and nutrient intake was examined. SUBJECTS: Using a multistage, stratified random sampling, 1,530 Canadian adults aged 19 to 65 years were surveyed. STATISTICAL ANALYSES PERFORMED: Intakes from diet, supplements, and diet plus supplements were examined by age/gender stratification. RESULTS: Supplement users had dietary intakes, from food alone, similar to nonusers with mean intakes in some age/sex groups below the Recommended Daily Allowance (RDA)/Adequate Intake (AI) for iron, calcium, and folate. Multivitamin users had mean intakes (from diet plus supplement) of folate above the RDA and iron intakes also increased to RDA levels among women aged 19 to 50 years. Calcium supplement users had lower calcium and vitamin D intakes than nonusers from diet alone in some age/sex groups. Calcium tablets increased mean calcium intakes to AI levels among all age/sex groups. Many supplement users exceeded the new Upper Limits of safe intake; 47% in the case of niacin. APPLICATIONS: Supplements are commonly used and can help some persons adhere to Dietary Reference Intake recommendations concerning intake of folate, calcium, vitamin D. and iron. We found multivitamin users to have higher total intakes of folic acid, iron, calcium, and vitamin D. Also, targeted use of calcium supplements effectively enhanced intakes. However, concurrent vitamin D supplementation is important and awareness of product composition with respect to Upper Limits is essential.     

Considerations on an Approach for Establishing a Framework for Bioactive Food Components

Bioactive food components have shown potential health benefits for more than a decade. Currently there are no recommended levels of intake [i.e., Dietary Reference Intakes (DRIs)] as there are for nutrients and fiber. DRIs for essential nutrients were based on requirements for each specific nutrient to maintain normal physiologic or biochemical function and to prevent signs of deficiency and adverse clinical effects. They were later expanded to include criteria for reducing the risk of chronic degenerative diseases for some nutrients. There are many challenges for establishing recommendations for intakes of nonessential food components. Although some nonessential food components have shown health benefits and are safe, validated biomarkers of disease risk reduction are lacking for many. Biomarkers of intake (exposure) are limited in number, especially because the bioactive compounds responsible for beneficial effects have not yet been identified or are unknown. Furthermore, given this lack of characterization of composition in a variety of foods, it is difficult to ascertain intakes of nonessential food components, especially with the use of food-frequency questionnaires designed for estimating intakes of nutrients. Various intermediary markers that may predict disease outcome have been used as functional criteria in the DRI process. However, few validated surrogate endpoints of chronic disease risk exist. Nonvalidated intermediary biomarkers of risk may possibly predict clinical outcomes, but more research is needed to confirm the associations between cause and effect. One criterion for establishing acceptable intermediary outcome indicators may be the maintenance of normal physiologic function throughout adulthood, which presumably would lead to reduced chronic disease risk. Multiple biomarkers of outcomes that demonstrate the same health benefit may also be helpful. It would be beneficial to continue to refine the process of setting DRIs by convening a workshop on establishing a framework for nonessential food components that would take into consideration intermediary biomarkers indicative of optimal health.     

Assessment of antioxidant nutrient intake of a population of southern US African-American and Caucasian women of various ages when compared to dietary reference intakes

Antioxidant nutrient intervention strategies to ameliorate negative health factors are of notable research interest. Central to the thesis that antioxidant nutrients improve biological defense systems and provide health benefits is an accurate indication of daily antioxidant nutrient intake. Little information is available concerning these nutrient intakes among non-affluent women of the southern U.S. This study examines the 24-h intake of vitamins: A, E, C, -carotene, a-tocopherol, riboflavin, and minerals: zinc, selenium, copper, manganese, iron, and molybdenum among 259 Caucasian (CA) and African-American (AA) women from small urban communities. Women were non-pregnant females, 19-93 y of age. Statistical comparisons of nutrient intake were made by least squares means within age groups. Intakes were compared to various Dietary Reference Intakes including Recommended Daily Allowance (RDA) and Estimated Average Requirement (EAR) values as established by the U.S. National Research Council. Numerous dietary deficiencies in important antioxidant nutrients associated with metabolic antioxidant systems were identified. Few race-related differences were detected. Intake of vitamin A was generally within recommended levels while vitamin E intake was below the EAR. The vitamin precursors, -carotene and a-tocopherol, were significantly (P<0.05) below customary intakes at all ages. More than 60% of this population reported dietary copper, zinc, and selenium intakes below recommended levels. A lack of race differences for most nutrient intakes suggests similar socioeconomic or endogeneous regional factors. All women in this population reported dietary intakes of antioxidant vitamins and minerals below recommended values, conditions that could contribute to subsequent health risks unless nutrient-dense food choices and antioxidant supplementation are considered in their overall nutritional support.     

Foods, fortificants, and supplements: Where do Americans get their nutrients?

Limited data are available on the source of usual nutrient intakes in the United States. This analysis aimed to assess contributions of micronutrients to usual intakes derived from all sources (naturally occurring, fortified and enriched, and dietary supplements) and to compare usual intakes to the Dietary Reference Intake for U.S. residents aged ≥2 y according to NHANES 2003-2006 (n = 16,110). We used the National Cancer Institute method to assess usual intakes of 19 micronutrients by source. Only a small percentage of the population had total usual intakes (from dietary intakes and supplements) below the estimated average requirement (EAR) for the following: vitamin B-6 (8%), folate (8%), zinc (8%), thiamin, riboflavin, niacin, vitamin B-12, phosphorus, iron, copper, and selenium (<6% for all). However, more of the population had total usual intakes below the EAR for vitamins A, C, D, and E (34, 25, 70, and 60%, respectively), calcium (38%), and magnesium (45%). Only 3 and 35% had total usual intakes of potassium and vitamin K, respectively, greater than the adequate intake. Enrichment and/or fortification largely contributed to intakes of vitamins A, C, and D, thiamin, iron, and folate. Dietary supplements further reduced the percentage of the population consuming less than the EAR for all nutrients. The percentage of the population with total intakes greater than the tolerable upper intake level (UL) was very low for most nutrients, whereas 10.3 and 8.4% of the population had intakes greater than the UL for niacin and zinc, respectively. Without enrichment and/or fortification and supplementation, many Americans did not achieve the recommended micronutrient intake levels set forth in the Dietary Reference Intake.     

Determination of vitamin B-6 estimated average requirement and recommended dietary allowance for children aged 7-12 years using vitamin B-6 intake,nutritional status and anthropometry

The Estimated Average Requirement (EAR) and Recommended Dietary Allowance (RDA) of vitamin B-6 for children were recently estimated by extrapolating from adult values because of limited available information. To determine vitamin B-6 requirements and provide recommendations for intakes, vitamin B-6 intake, nutritional status and anthropometry of 168 healthy children (79 boys and 89 girls) were studied in Tainan, Taiwan. Direct and indirect vitamin B-6 status indicators were measured in plasma, erythrocytes and urine. Anthropometric data of children in this study were similar to those of the first Nutrition and Health Survey in Taiwan (NAHSIT) conducted in 1993-1996. The plasma pyridoxal phosphate (PLP) concentration of each child was >/=30 nmol/L, indicating an adequate vitamin B-6 status. Daily dietary vitamin B-6 intakes of boys and girls were 0.80 +/- 0.16 and 0.74 +/- 0.16 mg/d, respectively. Daily dietary vitamin B-6 intakes of children who had adequate urinary 4-pyridoxic acid (4-PA) (>3.0 micro mol/L), erythrocyte alanine aminotransferase activity coefficient (EALT-AC) (<1.25) and aspartate aminotransferase activity coefficient (EAST-AC) (<1.8) were not different from those of children who had adequate plasma PLP, although the percentages of adequacy for urinary 4-PA, EALT-AC and EAST-AC ranged from 20 to 91%. Vitamin B-6 status indicators were strongly correlated with vitamin B-6 intake. Adequate values of PLP, EALT-AC, EAST-AC and urinary 4-PA were used to determine the EAR according to Dietary Reference Intake (DRI) committee methodology. We determined the vitamin B-6 EAR (RDA) for boys and girls aged 7-12 y to be 0.84 (1.01) and 0.75 (0.89) mg/d, respectively.     

Planning diets for individuals using the dietary reference intakes

Dietary Reference Intakes (DRIs) are now available for energy, macronutrients, fiber, vitamins, and minerals, and can be used to plan diets for individuals. This article defines the four DRIs (the Estimated Average Requirement, the Recommended Dietary Allowance, the Adequate Intake, and the Tolerable Upper Intake Level), and describes two other reference standards--the Estimated Energy Requirement and the Acceptable Macronutrient Distribution Range. Planning diets for individuals involves identifying the appropriate nutrient intake goals, translating the nutrient goals into food intake (and supplement use, if warranted), assessing the plan, and revising it if required. This process is illustrated using case studies of a female vegetarian marathon runner and an older male smoker.     

Seasonal variation of food consumption and selected nutrient intake in Linxian,a high risk area for esophageal cancer in China

Linxian, China, is a region with high incidence of esophageal cancer and a history of poor nutritional status. Nutrition Intervention Trials were conducted in this area from 1985 through 1991 and found a reduction in total cancer mortality in the group receiving supplementation of beta-carotene/selenium/alpha-tocopherol. The positive results of those trials have, in part, been ascribed to the poor nutritional status of this population. To investigate more recent food patterns, nutrient intakes, and seasonal variations in the diet, dietary surveys were conducted among the residents of Linxian in 1996. Food consumption data were collected among 104 households in spring and 106 households in autumn using a method of food inventory changes. Intake of nutrients was estimated and compared to the Chinese Recommended Dietary Allowance (RDA). In both seasons, the five most common food groups consumed were cereals, fresh vegetables, yams, seasoning, and eggs. Low nutrient intakes were found for selenium (79% RDA and 66% RDA), zinc (72% RDA and 62% RDA), vitamin B2 (64% RDA and 52% RDA), and calcium (53% RDA and 39% RDA) in both spring and autumn. A large seasonal variation was seen in the consumption of leafy vegetables, root vegetables and eggs, all of which might have contributed to the lower intake of vitamin A (25% RDA), vitamin C (75% RDA), protein (76% RDA), and vitamin E (78% RDA) in autumn. These indicate that the nutrient intake in Linxian is inadequate for a number of vitamins and minerals including those shown to be associated with esophageal cancer.     

Using DRIs for dietary assessment

Nutrient standards such as the Dietary Reference Intakes (DRIs) may be used to assess diets of both individuals and of population groups. The goal is to estimate the probability of dietary adequacy (or inadequacy) for an individual and the prevalence of dietary adequacy for a group. The DRI that is needed to estimate the probability of dietary adequacy is the estimated average requirement for a nutrient (EAR), as well as an estimate of the standard deviation of the requirement. The probability of adequacy for an individual should be based on usual long-term intake, because the DRIs apply to a person's usual intake, rather than to intake on only a few days. Due to day-to-day variation in intakes, it is usually necessary to record or observe a person's intake for a large number of days. For population groups, the prevalence of adequacy can be calculated as the average of each person's probability of adequacy, and should correspond to the proportion of the population with nutrient intakes exceeding nutrient needs. A short-cut method to estimating the prevalence of adequacy simply calculates the proportion of intakes that are above the EAR. It is not necessary to have usual long-term intake for each person in the group, but a statistical procedure must be used to remove the effect of day-to-day variation from the intake distribution before the prevalence of adequacy within a group is estimated. With the new DRIs, a more informative assessment of both individual and group intakes is possible.     

中国成年居民营养素摄入状况的评价

目的使用ISU方法计算营养素的日常摄入量(UI),评估中国成年居民的营养素摄入状况。方法使用"2002年中国居民营养与健康状况调查"数据,采用美国爱荷华州立大学(Iowa State Unirersity,ISU)方法计算43 672名成年居民的碳水化合物、蛋白质、钙、铁、锌、硒、镁、维生素B1和维生素B2的UI,并将UI与平均需要量(EAR)比较,评估这些营养素摄入不足的比例;将宏量营养素供能比的UI与可接受宏量营养素分布范围(AMDRs)或适宜摄入量(AI)比较,评估宏量营养素摄入是否合理。结果我国成年居民碳水化合物和蛋白质供能比UI均值均在推荐范围之内,脂肪供能比UI均值稍高于AI上限;碳水化合物供能比低于AI下限的比例约为40%,蛋白质供能比低于AMDRs下限的比例约为20%,脂肪供能比高于AI上限比例约为50%。我国成年居民钙、锌、硒、镁、维生素B1和维生素B2摄入不足比例均较高,其中钙摄入不足的比例超过95%,维生素B1和维生素B2摄入不足的比例均达到了80%以上。结论我国成年居民宏量营养素供能比例不合理,膳食钙、锌、硒、镁、维生素B1和维生素B2摄入不足状况较为严重。