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Executive Summary INTRODUCTION AND BACKGROUND Started in 1974, the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) was designed to meet the special nutritional needs of low-income pregnant, breastfeeding, or postpartum women; infants; and children up to 5 years of age who have at least one nutritional risk factor. The WIC Program provides three main benefits: supplemental foods, nutrition education, and referrals to health and social services. WIC food packages provide supplemental foods but the proportion of the total diet that is supplied through the package varies by participant category (see Chapter 1). The food is generally provided through food vouchers or checks that can be exchanged for specific foods at participating grocery outlets. Since the inception of the WIC program around 1974, substantial changes have occurred that make it important to review the WIC food packages. · Changes have occurred in the WIC population. The size and scope of the WIC Program have changed. The WIC program has grown substantially and the WIC participants are a very culturally diverse population. · Changes have occurred in the food supply and in dietary patterns. Since 1990 the number of food products in U.S. retail grocery stores has increased by approximately 60 percent. Women's intake of carbonated soft drinks has more than doubled since 1977-1978. · Changes have occurred in health concerns. Obesity has emerged as a major public health concern in both the general population and the population subgroups that participate in the WIC program. At the same time, a need still exists to ensure adequate nutrition during critical periods of growth and development. It is important to keep in mind that overweight or obesity can co- exist with inadequate intakes and even deficiencies of micronutrients. Addressing both the risk of overweight and obesity and prevention/remediation of undernutrition among vulnerable groups poses a challenge in terms of optimizing the potential contribution of the WIC food package. · Changes have occurred in nutrition knowledge and its application through dietary guidance and recommendations. Knowledge about the effects of diet on health has increased substantially in the past few decades. New dietary reference standards called Dietary Reference Intakes (DRIs) are available and may be used to evaluate both nutrient adequacy and nutrient excess. The number of nutrients included in the new standards and the recommended intakes of many of the nutrients have changed. The Dietary Guidelines for Americans have been published ES-1
ES-2 PROPOSED CRITERIA FOR SELECTING THE WIC FOOD PACKAGES every five years since 1980; each revision considers the most recent scientific knowledge to provide guidance on dietary patterns that promote health. Despite the external changes that have occurred since the inception of the WIC program, the only recent change in the WIC food packages was a small revision in the package for exclusively breastfeeding women. In proposing effective WIC food packages, the Committee is faced with many challenges that arise from the scientific, market, social, and health changes described above. Challenges also arise from other considerations such as current food safety concerns; participants' access to transportation, storage, and cooking facilities; and the impact on WIC administration and vendors related to modifications to established procedures. COMMITTEE'S TASK The U.S. Department of Agriculture's Food and Nutrition Service has charged the Committee, through the Institute of Medicine's Food and Nutrition Board, to conduct a two- phase evaluation of the WIC food packages. In Phase I, summarized in this preliminary report, the Committee's specific tasks are to review nutritional needs of the population subgroups participating in the WIC program using scientific methods summarized in the Dietary Reference Intake reports, assess supplemental nutrition needs of these subgroups, and propose priority nutrients and general nutrition recommendations for the WIC program. In Phase II, the Committee will apply the findings of this assessment to develop recommendations for specific changes to the WIC food packages. This preliminary report presents the results of the Phase I tasks, and proposes the priorities and criteria that will be used to recommend changes to the WIC food packages during Phase II of the project. In Phase I of the project, the Committee considered evidence of three major types: analyses of the nutrient intake of WIC-eligible populations (described in Chapter 3); analyses of the food intake of WIC-eligible populations (described in Chapter 4); and nutrition-related health risks and outcomes of WIC-eligible populations (described in Chapter 5). By utilizing and integrating all three of these approaches, when possible, the Committee attempted to overcome the limitations of any one approach applied individually. It was not feasible to include all categories of WIC participants in every type of analyses because the appropriate data set was not always available. For example, sufficient dietary intake data for breastfed infants were not available for the nutrient analyses described in Chapter 3; however, breastfed infants were considered in the analyses of nutrition-related health risks and outcomes described in Chapter 5. It was not feasible to include all nutrients in every type of analyses because the appropriate data were not available. For example, intake data for vitamin D and folate were not available for the nutrient analyses described in Chapter 3; however, vitamin D and folate were considered in the analyses of nutrition-related health risks and outcomes described in Chapter 5. NUTRIENT INTAKE OF WIC-ELIGIBLE POPULATIONS Because published evaluations comparing the nutrient intakes of WIC-income-eligible populations to the new DRIs were not available, the Committee conducted analyses of the nutrient adequacy of the diets of WIC-income-eligible subgroups--infants under one year of age, children ages 1 through 4 years, and women of reproductive age--from households with incomes in the range that is eligible for the WIC program. Although many of these households are already receiving WIC benefits, the intent of the analyses was to identify nutrients of concern to guide
EXECUTIVE SUMMARY ES-3 the Committee in recommending specific changes in the food packages during phase II of the project. The term "nutrient of concern" signifies that, if feasible, the revised food packages will improve intake of that nutrient. The analyses conducted for this report utilized 24-hour dietary recall data from the 1994-1996 and 1998 Continuing Survey of Food Intakes by Individuals (CSFII) and methods recently published by the Institute of Medicine to assess the nutrient adequacy of diets. Nutrient adequacy was examined by determining the estimated prevalence of inadequate intakes for eight micronutrients (calcium, iron, zinc, magnesium and vitamins A, C, E, and B6), potassium, dietary fiber, and protein. Possible excessive intakes were examined for food energy (the caloric content of the diet), percentage of food energy from fat, and intakes of sodium, added sugar,1 and several micronutrients (calcium, iron, zinc and vitamins A, C, and B6). Although intake data are biased to some extent by under-reporting in data for adults and over-reporting in data for children, these data permit a ranking of nutrients likely to be inadequate or excessive within each of the WIC target populations. For example, although there are limitations to intake estimates for vitamin E, the very high prevalence of inadequate intakes cannot be ignored. Additionally, although the application of the DRIs has not been thoroughly tested and enhanced in the iterative process envisioned, it provides the Committee with the best documented approach to identifying nutrients of concern. Based on the Committee's analyses of available data, priority nutrients of concern because of inadequate intake are: · Infants, non-breastfeeding: none · Children 1 through 4 years of age: vitamin E, potassium, and fiber · Adolescents and adult women of reproductive age: Highest priority--calcium, magnesium, vitamin E, potassium, and fiber Next in priority--vitamins A, C, and B6 Based on the Committee's analyses of available data, nutrients that may be excessive in diets are: · Infants, non-breastfeeding: zinc and preformed vitamin A. Food energy intake may exceed energy needs. · Children 1 through 4 years of age: zinc, preformed vitamin A, and sodium. Food energy intake may exceed energy needs. · Adolescent and adult women of reproductive age: sodium, food energy, and total fat intake as a percentage of food energy. FOOD INTAKE OF WIC-ELIGIBLE POPULATIONS The Dietary Guidelines for Americans provide science-based advice to promote health and to reduce risk for major chronic diseases through diet and physical activity. They are targeted to healthy people two years of age and older. According to Public Law No. 101-445 (U.S. Congress, 1990), the Dietary Guidelines form the basis of federal food assistance, nutrition education, and information programs, including the WIC program. The USDA food pattern recommendations that accompany the Food Guide Pyramid, issued in 1992, were designed to reflect the Dietary Guidelines. The Committee compared food group intakes with recommendations from the Food Guide Pyramid to assess food patterns of low-income children and women of childbearing age. In 1 Added sugars have been defined by USDA as sugars and syrups that are added to foods during processing or preparation. See Chapter 3 for a description of the term "added sugars."
ES-4 PROPOSED CRITERIA FOR SELECTING THE WIC FOOD PACKAGES general, for four of the food groups (grains, vegetables, fruits, and dairy) fewer than 50 percent of children, adolescents, and women met the recommended minimum. Also, fewer than 50 percent of the adolescents and women met the recommended minimum for the meat and meat alternatives group. For children 2 to 5 years of age, percentages meeting the recommended minimum were lowest for the vegetable group. For women of childbearing age, percentages meeting the recommended minimum were lowest for the fruit and dairy groups. Compared to Food Guide Pyramid allowances, intakes of added sugars were high for all groups for which data were available. Since children under the age of two years are not generally included in dietary guidance for the general population, different sets of guidance were considered. A major finding for infants was that breastfeeding rates for WIC mothers have increased--more than 50 percent of WIC women now initiate breastfeeding--but the duration of breastfeeding was much shorter than the American Academy of Pediatrics recommendation of one year (see Chapter 4). Another finding that impacts children ages 12 to 24 months is that their diets lack variety and the mechanisms that promote acceptance of a variety of foods are lacking. For example, juice is by far the major form of food ingested from the fruit group but only a few select juices are consumed on a regular basis. Priorities for the revised WIC food packages include improving the contribution of the package to an overall dietary pattern that is consistent with the Dietary Guidelines (emphasizing the vegetable group for children, emphasizing the fruit and dairy groups for women, limiting the amount of added sugars, saturated fat, cholesterol, and trans fatty acids), further promoting breastfeeding of infants, and keeping juice allowances within recommendations. NUTRITION-RELATED HEALTH RISKS AND OUTCOMES OF WIC-ELIGIBLE POPULATIONS Nutrients of concern in the WIC-eligible populations also were identified by examining health risks that are specific to infants, young children, and women of reproductive age. Growing rates of overweight and obesity among low-income adolescent and adult women are of particular concern. Although the cause of obesity has many facets, the common denominator is positive energy balance. In order to promote a healthy body weight at each life stage, the overall energy balance between physical activity and food energy intake must be considered in prescribing an appropriate food package for each individual. Thus, flexibility to promote food energy intakes over a healthy range should be considered in formulating the food package allowances from which an individual's prescription will be drawn. Although intakes of folate and vitamin D could not be evaluated using data from the CSFII, information from other sources indicates that these should be priority nutrients in the WIC food package. Adequate dietary folate prior to and early in pregnancy is crucial for reducing the risk of neural tube defects, yet many women fail to obtain recommended intakes. Vitamin D is needed for bone health in women, yet evidence suggests that intakes are low. Although dietary iron inadequacy was not identified as a significant problem in WIC-income-eligible children, there is biochemical evidence from clinical laboratory data that iron deficiency remains above the goal for reduction of iron deficiency in children as outlined it the Healthy People 2010 initiative (see Chapter 5). Although dietary iron inadequacy was identified at a low level of concern for low-income women of reproductive age, biochemical evidence from clinical laboratory data that iron deficiency remains a problem with women in this life stage raises iron to a nutrient of concern (see Chapter 5).
EXECUTIVE SUMMARY ES-5 Health risks related to environmental exposures are also a concern for the WIC food package. Recent recommendations to reduce exposure to dioxin and dioxin-like compounds suggest that low-fat and non-fat dairy products should replace higher-fat alternatives, particularly for girls and women throughout the pre-reproductive and reproductive years. Exposure to methylmercury can be reduced by limiting intakes of certain types of fish that accumulate these compounds. The adverse effects of lead exposure may be somewhat mitigated by a diet that contains at least the recommended intake of calcium. PROPOSED PRIORITY NUTRIENTS AND FOOD GROUPS FOR THE WIC FOOD PACKAGES The Committee considered the results from each type of analysis (analyses of nutrient intakes of WIC-eligible populations, analyses of food intake of WIC-eligible populations, and consideration of nutrition-related health risks and outcomes in the WIC population). After evaluating the strengths and weaknesses of each approach, the proposed priority nutrients and food groups were selected, and are summarized in Table ES-1.
ES-6 PROPOSED CRITERIA FOR SELECTING THE WIC FOOD PACKAGES TABLE ES-1 Proposed Priorities for the WIC Food Packages Nutrients of Participant Proposed Priority Proposed Priority Concern with Nutrients to Limit Category Nutrients Food Groups Regard to in the Diet Excessive Intake Infants, less than 1 year of age, non-breastfed N/A Zinc Vitamin A, preformed 1 Food energy Infants, 6 through 11 months of age, breastfed Iron N/A Zinc Children, 12 through 23 months of age Iron Vegetables Zinc Vitamin E Vitamin A, Potassium Fiber preformed 1 Sodium Food energy Children, 2 through 4 years of age Iron Vegetables Zinc Saturated fat Vitamin E Vitamin A, Cholesterol Fiber preformed 1 Potassium Sodium Food energy Adolescent and adult women of reproductive age Highest priority: Fruit Sodium Saturated fat Calcium Dairy products, Food energy Cholesterol Iron low-fat or Total fat Trans fatty acids 2 Magnesium nonfat Vitamin E Fiber Potassium Also consider: Vitamin A Vitamin C Vitamin D Vitamin B6 Folate NOTE: N/A = not applicable from available data. 1The UL applies only to preformed vitamin A (i.e., retinol) ingested from the combined sources of animal- derived foods, fortified foods, and dietary supplements. 2Trans fatty acids have not specifically been identified as a hazard for infants and children, and thus are shown in the table as nutrients to limit only in the diets of adolescents and adults. However, the recommendation to limit trans fatty acids from processed foods in the diet is presumed to apply to all individuals regardless of age.
EXECUTIVE SUMMARY ES-7 PROPOSED APPROACH FOR SELECTING THE WIC FOOD PACKAGES The criteria shown in Box ES-1 are proposed for use in selecting the revised WIC food packages. Both a cost evaluation and an evaluation of benefits and risks will be performed for the proposed revisions to the WIC food packages. The goal is to propose food packages that improve the health of the WIC population with minimal impact on costs, vendors, and WIC agencies. The identification of these proposed priority nutrients and food groups and these proposed criteria represents the first phase in the Committee's two phase task of recommending specific changes to the food packages. BOX ES-1 Proposed Criteria for a WIC Food Package, if Consumed as Specified 1. The package reduces the prevalence of inadequate nutrient intakes and of excessive nutrient intakes. 2. The package contributes to an overall dietary pattern that is consistent with the Dietary Guidelines for Americans for individuals two years of age and older. 3. The package contributes to an overall diet that is consistent with established dietary recommendations for infants and children less than two years of age, including encouragement and support for breastfeeding. 4. The foods in the package are available in forms suitable for low-income persons who may have limited transportation options, storage, and cooking facilities. 5. The foods in the package are readily acceptable, commonly consumed, are widely available, take into account cultural food preferences, and maintain the incentive value of the food packages for families to participate in the WIC Program. 6. The foods will be proposed giving consideration to the impact of changes in the package on vendors and WIC agencies.
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