4

Nutrient Intakes of WIC-Eligible Populations

In phase I, the committee was tasked with assessing nutrient intakes of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC)-eligible populations. The committee first conducted a review of the literature specific to WIC participants. Next, the committee analyzed National Health and Nutrition Examination Survey (NHANES) data to evaluate current nutrient intakes among WIC-eligible women, infants, and children in comparison to the Dietary Reference Intakes (DRIs) (using NHANES 2011–2012 data) and to compare intakes between WIC participants and income-eligible nonparticipants (using 2005–2008 NHANES data). Chapter 5 provides data on food group intakes of these same groups. In combination, these analyses support identification of nutrient and food group priorities for the WIC food packages. Details of the methodologies used for these tasks were presented in Chapter 3. The results of the literature search, NHANES analyses, and nutrient profile estimates are summarized here.

LITERATURE AND REPORT FINDINGS: NUTRIENT INTAKES

This section summarizes the committee’s literature and report findings regarding nutrient intakes among WIC participants. Chapter 6 provides additional details about the prevalence of nutrient inadequacy and excess, on a per-nutrient basis, for mothers (before, during, and after pregnancy), infants, and children (less than 5 years of age).

Literature Findings on Change in Nutrient Intakes Since the 2009 Food Package Change

Few studies in the published literature have reported the nutrient intakes of WIC participants. The committee identified three reports that compared nutrient intakes before and after the 2009 WIC food package revisions. Odoms-Young et al. (2014) assessed dietary intake of 273 Hispanic and African American children ages 2 to 3 years from 12 WIC clinics in Chicago both before and after the food package changes. They found that Hispanic children had reduced saturated fat and increased fiber intakes following the food package changes. African American children significantly increased their caloric intake. Kong et al. (2014) collected data immediately before the food package revisions and 18 months post-revision and found decreases in total and saturated fat and increases in dietary fiber and overall diet quality among Hispanic children only. No significant changes in nutrient intake were observed for any other group. Thornton et al. (2014) reported results from a small study (2009, n = 84; 2011, n = 120) in central Texas among children ages 4 to 24 months. They found lower energy intakes after the food package changes. Mean usual intakes of retinol and zinc exceeded the Tolerable Upper Intake Level (UL) for all groups, although the proportion of individuals exceeding the UL for zinc decreased after the package changes.

In summary, some beneficial changes in food intake after the introduction of the new food packages were identified in all of these studies, but specific findings were inconsistent from study to study. It is noteworthy that the committee was unable to identify any published studies of nutrient intake in WIC participating women or infants apart from the U.S. Department of Agriculture’s Food and Nutrition Service (USDA-FNS) (USDA/FNS, 2015) for which sample sizes for women and for infants were unreliably small as noted below.

Diet Quality of American Young Children: USDA-FNS Report

The committee reviewed the recently released USDA-FNS report Diet Quality of American Young Children by WIC Participation Status (USDA/FNS, 2015), which used the same NHANES 2005–2008 data that were examined in this report. In both cases, nutrient intakes were compared to the appropriate age-specific DRIs. The committee used these reported nutrient intakes for comparison with estimates generated by its own NHANES analyses. However, there were two methodological differences relevant to nutrient intake estimation between the USDA-FNS analysis and the analysis conducted here. First, the committee examined WIC participating compared to WIC-eligible nonparticipating children, but USDA-FNS analyzed three subgroups of children: WIC, non-WIC lower income (≤ 185 percent of pov-

erty), and nonparticipating higher income children. Second, the committee applied the Iowa State University (ISU) method while USDA-FNS applied the National Cancer Institute method for usual intake estimation and also made statistical comparisons when possible. The USDA-FNS report focused on children ages 1 to less than 5 years of age because the samples for infants and FOR women were too small to yield reliable estimates. Nutrient intake results in the USDA-FNS (2015) report are presented in Appendix O and summarized briefly here.

A key finding of USDA-FNS report was that large proportions of children ages 1 to less than 5 years old had inadequate intakes of vitamin E as well as vitamin D and calcium. Non-WIC-participating higher-income children were significantly more likely to have lower vitamin E intakes than WIC participating children. Mean potassium and fiber intakes were below the adequate intakes (AIs)¹ for these nutrients across all groups. The majority (74 percent) of all children had excessive intakes of sodium.

For macronutrients, intakes of total fat were outside the appropriate range for 30 percent of children and their intakes and were more likely to be too low than too high. Saturated fat intakes were above recommended levels for 83 percent of children. Consumption of energy from “empty calories” (i.e., solid fats and added sugars) was two to three times the recommended UL of 10 to 14 percent of total calories.

NHANES ANALYSIS: NUTRIENT INTAKES

This section presents intakes of micronutrients, macronutrients, and energy for three groups (2005–2008 WIC participants, 2005–2008 income-eligible nonparticipants, and 2011–2012 low-income individuals) across relevant WIC age categories (pregnant, breastfeeding, and postpartum women, 19 to 50 years; formula-fed infants 0 to less than 6 months; formula-fed infants 6 to less than 12 months; children 1 to less than 2 years; and children 2 to less than 5 years). Too few breastfeeding infants with reported food intake were included in NHANES to estimate their usual intakes of foods for any survey years of interest. Micronutrient, macronutrient, and energy intake means and distributions of the adequacy percentages discussed in this chapter are presented in Appendix P.

Although USDA-FNS was interested in comparing intakes among WIC participants before and after the 2009 food package change, the indicator of WIC participation for the NHANES 2011–2012 dataset became available only after completion of these analyses. Therefore, a comparison of nutrient intakes among WIC participants before the 2009 food package

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¹ Definitions of adequate intake (AI) and other Dietary Reference Intake (DRI) values are provided in Chapter 3, Box 3-1.

changes to those after the changes could not be conducted. Moreover, only the 2005–2008 NHANES data were considered appropriate for comparison of WIC participants to WIC-eligible nonparticipants.² All individuals who were income-eligible for WIC from NHANES 2011–2012 were analyzed as a proxy for WIC participants. In phase II, the WIC indicator will be applied to the NHANES 2011–2012 dataset so that, depending on the sample sizes in 2011–2012, intakes of WIC participants in 2011–2012 can be compared to those of income-eligible nonparticipants. With adequate sample sizes, WIC participant intakes can also be compared before and after the 2009 food package changes.

Nutrient intakes were compared to the DRI references values appropriate for evaluation of groups, the Estimated Average Requirement (EAR) or the AI values, the UL, and the Acceptable Macronutrient Distribution Range (AMDR). PC Software for Intake Distribution (PC-SIDE) was used to implement the ISU method of determining usual nutrient intake distributions. The methods used to conduct these analyses of NHANES data are described in detail in Chapter 3. As indicated in Chapter 3, the prevalence of inadequacy or excess was estimated by determining the proportion of persons in the group whose usual intakes do not reach the EAR, fall outside of the AMDR, or exceed the UL. When combining groups with different EARs, intakes in one of the groups were rescaled so they can be compared to the EAR of the other group (IOM, 2000a). This re-scaling approach was applied to the group with children 1 to less than 5 years of age, and to the combined group of pregnant, breastfeeding, and postpartum women (IOM, 2001). No conclusion can be drawn about the prevalence of inadequacy for an intake level that falls below the AI (IOM, 2000a); therefore, mean intake values are presented for these nutrients.³ Intakes of macronutrients that fall above or below the AMDR may increase the risk of chronic disease. A prevalence of inadequacy or excess greater than 5 percent was considered of concern.⁴ Vitamin D intake data are presented only for infants ages 0 to less than 12 months because serum vitamin D data are not available for this

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² In addition to the difficulties with separation of the 2009–2010 NHANES dataset, this period spanned the change in food packages. It was therefore not considered appropriate for either the pre- or post-food package change assessments.

³ Prevalence of inadequacy is presented for nutrients with an EAR. For nutrients with an AI only, interpretation of intake comparisons differs. If mean usual intake meets or exceeds the AI, it can only be said that the prevalence of inadequacy in the population group is likely to be low (IOM, 2000a). Therefore, for nutrients with an AI, the mean intake data are presented.

⁴ As described in Chapter 3, a concerning level of inadequate or excessive intake of any nutrient is usually defined as less than 2.5 percent of the population of interest (IOM, 2003). This percentage should translate to an equivalent percentage of impaired function or adverse effect. For this report, a 5 percent threshold was applied. This is a slightly relaxed standard, which accounts for some of the uncertainty in setting the EARs, as well as some of the generally accepted errors associated with dietary assessment.

age group. Vitamin D intake data are not presented for other age groups because of the limited utility of intake information for the assessment of adequacy (Taylor et al., 2013). In phase II, the effects of potential food package changes on vitamin D content of the packages will be assessed in the sensitivity analysis.

For several population subgroups, the sample size is small (i.e., for eligible non-WIC infants 0 to less than 6 months of age, n = 21). Although the mean is adequately precise with small sample sizes in these NHANES datasets (except for the women’s subgroup in 2011–2012), intake estimates falling at the ends of the distributions are less precise. For the small subgroup of women, a variance adjustment was applied to reduce the effect of variability in within-person variance (described below and in Chapter 3). WIC participant and eligible non-WIC participant subgroups were compared by t-test. One consequence of the small sample sizes is that the standard error values are large and thus only large differences between means can be detected.

Nutrient Intake of Pregnant, Breastfeeding, and Postpartum Women, Ages 19 to 50 Years

As described in Chapter 3, the sample sizes for pregnant, lactating, and postpartum women were small; therefore respondents of all physiological stages were combined into one analytical subgroup. In addition, the external variances were adjusted by the method of Jahns et al. (2005) to produce estimates that were less subject to the large degree of variability in the within-person variance estimate that can be introduced by a small sample size (described in Chapter 3). The re-scaling method was applied to accommodate differences in nutrient requirements for these various physiological states. There were no statistically significant differences among WIC-participant and eligible nonparticipant subgroups.

Micronutrient Adequacy

For pregnant, breastfeeding, and postpartum women, the prevalence of inadequacy was greater than 5 percent for most nutrients across all subgroups: calcium, copper, iron, magnesium, zinc, thiamin, folate, and vitamins A, E, C, and B6 (see Table 4-1). Low riboflavin and niacin intakes were present in a smaller percentage of women (6 to 9 percent) in the 2005–2008 dataset, but not in the most recent dataset. Micronutrients with the highest prevalences of inadequacy were vitamin E (88 to 98 percent across groups), vitamin A (58 to 60 percent), iron (39 to 66 percent), and magnesium (47 to 65 percent). Vitamin C inadequacy was also present in at least 30 percent of each subgroup analyzed.

TABLE 4-1 Estimated Prevalence of Inadequacy of Selected Nutrients Compared to the Estimated Average Requirement (EAR), Pregnant, Breastfeeding, and Postpartum Women, 19 to 50 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: αTOC = α-tocopherol; DFE = dietary folate equivalent; EAR = Estimated Average Requirement; N = sample size; NPNL/P/BF = Nonpregnant, nonlactating/pregnant/breastfeeding; RAE = retinol activity equivalent; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

^a % Inadequacy = percentage of individuals with usual intake below the EAR.

^b The approach of IOM (2000) was applied in which, when combining groups with different EARs, intakes in one of the groups are rescaled so they can be compared to the EAR of the other group. Values represent the NPNL/P/BF groups. One value indicates that the EAR is the same across groups.

Subgroup definitions are as follows:

^c WIC = All individuals reporting participation in WIC regardless of income level. Some women reporting WIC participation did not report being pregnant, breastfeeding, or postpartum.

^d Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^e All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

^f The EAR for NPNL women 19–30 years is 255 and for women 31–50 years it is 265. The EAR for P women 19–30 years is 290 and for the EAR for P women 31–50 years is 300; The EAR for BF women 19–30 years is 255 and for BF women 31–50 years the EAR is 265.

^g The EAR for NPNL women 19-30 years is 1.1 and for women 31-50 years is 1.3. SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). EARs are from Dietary Reference Intake reports (IOM, 1997, 1998, 2000, 2001, 2002/2005, 2005, 2011).

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). EARs are from Dietary Reference Intake reports (IOM, 1997, 1998, 2000, 2001, 2002/2005, 2005, 2011).

Intakes of Nutrients with an AI

Among nutrients with AIs, mean usual intakes of potassium and choline were below the AI across all subgroups (see Table 4-2).

Macronutrient and Energy Intake

Protein intakes for women were low, with the prevalence of inadequacy ranging from 24 to 38 percent across subgroups (see Table 4-3). Total fat intakes expressed as a percentage of calories, however, were high across all groups, with 49 percent of 2011–2012 low-income women having intakes above the AMDR. Excessive energy from total fat was more prevalent for WIC participating (39 percent) compared to WIC-eligible nonparticipating women (18 percent). Approximately 11 percent of women across all subgroups had excessive energy from saturated fat. The prevalence of low percentage of energy from carbohydrate was high only for WIC participants (11 percent), compared to 3 percent for eligible nonparticipants. Given that lowering or raising the percent of energy from one dietary macronutrient affects the contribution of the others, it is possible that the prevalence of excessive energy intakes from total fat is related to the prevalence of low energy intakes from carbohydrate. However, as recommended in the Scientific Report of the 2015 Dietary Guidelines Advisory Committee (2015 DGAC report) the focus for this age group should be ensuring that the intake of energy from saturated fat is below 10 percent (USDA/HHS, 2015). The 2015 DGAC report did not include any recommendations on energy from total fat or from carbohydrates. As shown in Table 4-3, all three of the subgroups examined here reported a mean energy intake from saturated fat that was slightly above the recommended 10 percent.

Mean fiber intakes for women were below the AI, and mean intakes of added sugars were excessive across all subgroups. Reported energy intake data are presented in Table 4-4. Mean usual intakes were higher than the calculated Estimated Energy Requirements (EERs) for WIC-eligible nonparticipating women and 2011–2012 low-income women, but not for WIC

TABLE 4-2 Estimated Mean Usual Intakes of Selected Nutrients Compared to the Adequate Intake (AI) Value, Pregnant, Breastfeeding, and Postpartum Women, 19 to 50 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: AI = Adequate Intake; N = sample size; NPNL/P/BF = Non-pregnant, non-lactating pregnant/breastfeeding; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

^a Values represent the AI for NPNL/P/BF groups. One value indicates that the AI is the same across groups.

Subgroup definitions are as follows:

^b WIC = All individuals reporting participation in WIC regardless of income level. Some women reporting WIC participation did not report being pregnant, breastfeeding, or postpartum.

^c Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^d All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). AIs are from Dietary Reference Intake reports (IOM, 1998, 2005).

TABLE 4-3 Estimated Intakes of Macronutrients Compared to Recommended Intakes, Pregnant, Breastfeeding, and Postpartum Women, 19 to 50 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: AI = Adequate Intake; AMDR = Acceptable Macronutrient Distribution Range; DRI = Dietary Reference Intake; EAR = Estimated Average Requirement; g/d = grams per day; g/kg/d = grams per kilogram of body weight per day; kcal = kilocalories; N = sample size; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

^a Values represent a DRI except for added sugars and saturated fat, for which values represent the recommended upper limit of daily intake for a 2,200 kcal diet.

Subgroup definitions are as follows:

^b WIC = All individuals reporting participation in WIC regardless of income level. Some women reporting WIC participation did not report being pregnant, breastfeeding, or postpartum.

^c Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^d All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

^e The protein EAR for adults is 0.66 g/kg/d,0.88 g/kg/d for pregnancy, and 1.05 g/kg/d for breastfeeding. The approach of IOM (2000) was applied in which, when combining groups with different DRIs, intakes in one of the groups are rescaled so they can be compared to the DRI of the other group.

^f Values represent the AI for nonpregnant, nonlactating/pregnant/breastfeeding women.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). Reference intakes for protein, total carbohydrate, total fat, and fiber are from the Dietary Reference Intake report (IOM, 2002/2005). Reference intakes for saturated fat and added sugars are from the Scientific Report of the 2015 Dietary Guidelines Advisory Committee (USDA/HHS, 2015).

TABLE 4-4 Estimated Usual Energy Intake and Estimated Energy Requirements, Pregnant, Breastfeeding, and Postpartum Women, 19 to 50 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: EER = Estimated Energy Requirement; kcal = kilocalories; N = sample size; SE = standard error.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level. Some women reporting WIC participation did not report being pregnant, breastfeeding, or postpartum.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

^d EERs were calculated assuming a low-active physical activity level. For pregnant women, EER calculations assumed the second trimester. For lactating women, EER calculations assumed the first 6-month period postpartum.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). EERs were calculated according to Dietary Reference Intake report (IOM, 2002/2005).

participating women. These findings should be interpreted with caution because reported energy intakes are known to be inaccurate (Subar et al., 2015) and mean intakes could also be affected by differing proportions of pregnant, lactation, and postpartum women within each subgroup.

Micronutrient Excess

The prevalence of excessive sodium intakes was high (84 to 92 percent) in all subgroups of women (see Table 4-5). Excess iron intakes were evident in only slightly more than 5 percent of subgroups, except for low-income women in the most recent dataset in which 13 percent of women exceeded the UL.

TABLE 4-5 Estimated Prevalence of Micronutrient Excess Compared to Tolerable Upper Intake Level (UL), Pregnant, Breastfeeding, and Postpartum Women, 19 to 50 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: N = sample size; SE = standard error; UL = Tolerable Upper Intake Level. Not included in table: percentages above the UL for these nutrients were < 0.01%: copper, phosphorus, selenium, zinc, retinol, vitamin C, vitamin B6, folic acid, and choline. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level. Some women reporting WIC participation did not report being pregnant, breastfeeding, or postpartum.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data are from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). ULs from Dietary Reference Intake reports (IOM, 1998, 2001, 2005, 2011).

Nutrient Intakes of Formula-Fed Infants

No data on the nutrient intakes of breastfed infants are presented because their intake of human milk was not measured in NHANES, and information on intake of other foods is available for very few of them. As a result, this section applies exclusively to infants who were coded as “formula-fed” in the NHANES dataset (intake of human milk may be occurring in these infants, but is unknown). The nutrient intakes of formula-fed infants were analyzed in two age groups: (1) from birth to less than 6 months of age, and (2) from 6 to less than 12 months of age. These groups align with the recommended age for introduction of complementary feeding (about 6 months [AAP, 2014]) and also the current age categories for the WIC food packages for infants (see Appendix D, Table D-1). Intakes for each age group are summarized separately below. Intake distributions for both age groups are presented in Appendix P. For infants, differences between WIC participants and WIC-eligible nonparticipants were not significant.

Formula-Fed Infants 0 to Less Than 6 Months of Age

Micronutrient intake compared to AIs Only AI levels (and not EARs) apply to infants from birth to less than 6 months of age (i.e., EARs were not available). These AIs are presented in Table 4-6 along with mean usual intakes for each nutrient. Mean usual intakes for all nutrients exceeded these AIs, except for choline. Intakes of choline were below the AI in all subgroups.

Macronutrient and energy intake Macronutrient and energy intake of infants up to 6 months of age are presented in Table 4-7. Mean intake of carbohydrates, fat, and protein were similar across subgroups. Mean intakes of protein, carbohydrate, and total fat exceed the AI for these nutrients. The mean usual energy intake of WIC participating infants less than 6 months of age was 705 kcal per day, which is 19 percent higher than the EER of 594 kcal per day for these individuals (see Table 4-8).

Micronutrient excess The prevalence of excessive micronutrient intakes compared to the UL for infants in this age subgroup are presented in Table 4-9. UL values have been defined only for calcium, iron, selenium, retinol, and zinc. Excess zinc intakes occur in more than 90 percent of the formula-fed infants in this analysis. As described in Chapter 3, zinc and retinol intakes above the established ULs are not considered of concern because the method used to set the UL resulted in a narrow margin between the Recommended Dietary Allowance (RDA) and the UL (IOM, 2001). There is no evidence for adverse effects from zinc naturally occurring in food, and retinol toxicity unless from supplemental sources is rare (IOM, 2001). The committee considers infant formula (and zinc provided therein) to be tightly regulated for safety by the U.S. Food and Drug Administration (FDA). Calcium intakes exceeded the UL for 10 percent of young infants only in the 2011–2012 low-income group.

Formula-Fed Infants 6 to Less Than 12 Months of Age

Micronutrient adequacy For micronutrients with EARs, inadequacy is defined as having an intake below the EAR. Micronutrient EARs for this age group have been established only for zinc and iron (see Table 4-10). The prevalence of inadequate zinc intake was low across all subgroups. Differences between WIC participants and eligible nonparticipants in this age group were not statistically significant.

Intake of nutrients with an AI Mean usual intakes of micronutrients without EARs fell close to the AI for choline and above their respective AIs for all other nutrients (see Table 4-11).

TABLE 4-6 Estimated Mean Usual Intakes of Selected Micronutrients Compared to Adequate Intake (AI) Values, Formula-Fed Infants Less Than 6 Months of Age, NHANES 2005–2008 and 2011–2012

NOTES: αTOC = α-tocopherol; AI = Adequate Intake; DFE = dietary folate equivalent; N = sample size; RAE = retinol activity equivalent; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals that did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data are from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). AIs are from Dietary Reference Intake reports (IOM, 1997, 1998, 2000, 2001, 2002/2005, 2005, 2011).

TABLE 4-7 Estimated Mean Intakes of Macronutrients, Formula-Fed Infants Less Than 6 Months of Age, NHANES 2005–2008 and 2011–2012

NOTES: AI = Adequate Intake level; g/kg/d = grams per kilogram of body weight per day; kcal = kilocalories; N = sample size; NA = data not available; NR = no recommendation; SE = standard error; tsp-eq/d = teaspoon-equivalents per day. Intake data were insufficient to calculate reliable estimates for fiber intakes. There were no statistically significant differences between the WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

^d All NA notations indicate that data are not available because Statistical Program for Age-adjusted Dietary Assessment (SPADE) requires more than two observations per group with two non-zero intakes in order to estimate a within-person variance.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). Reference intakes for protein, total carbohydrate, and total fat are per the Dietary Reference Intake report (IOM, 2002/2005).

Macronutrient and energy intake As was the case for younger infants, intakes of carbohydrate, fat, and protein were similar across all subgroups (see Table 4-12) (p > 0.1). For children 6 to less than 12 months of age, there is a DRI only for protein (11 g per day, as the RDA or 1.0 g/kg per day as the EAR). Nearly 100 percent of the infants in this age group exceeded the DRI for protein, with usual mean intake of 24 g per day (see Appendix P, Tables P-22 to P-24). Reported mean usual energy intake exceeded the calculated EER for all subgroups and was similar among the subgroups (see Table 4-13).

TABLE 4-8 Estimated Usual Energy Intake and Estimated Energy Requirement, Formula-Fed Infants Less Than 6 Months of Age, NHANES 2005–2008 and 2011–2012

NOTES: EER = Estimated Energy Requirement; kcal = kilocalories; N = sample size; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). EERs were calculated according to Dietary Reference Intake report (IOM, 2002/2005).

Micronutrient excess Across all subgroups, 86 to 89 percent of infants ages 6 to less than 12 months exceeded the UL for zinc, 29 to 36 percent exceeded the UL for retinol, and approximately 7 percent exceeded the UL for selenium (see Table 4-14). As noted for infants 0 to less than 6 months of age, zinc and retinol intakes above the UL are not considered of concern for this age group. Although 9 percent of WIC-eligible nonparticipating infants exceeded the UL for calcium, few WIC participating infants had intakes that were too high.

Evaluation of iron and energy provided in the WIC food packages for fully formula-feeding infants WIC formula is required to contain a minimum of 1.5 mg iron per 100 kilocalories at standard dilution⁵ (USDA/FNS, 2014). Participating formula-fed WIC participating infants ages 0 to 3 months old

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⁵ The FDA regulatory requirements for iron range from 0.15 to 3 mg per 100 mL (21 CFR § 107.100).

TABLE 4-9 Estimated Prevalence of Micronutrient Excess Compared to the Tolerable Upper Intake Level (UL), Formula-Fed Infants Less Than 6 Months of Age, NHANES 2005–2008 and 2011–2012

NOTES: N = sample size; SE = standard error; UL = Tolerable Upper Intake Level. Less than 0.01 percent of all population subgroups had iron, or selenium intakes exceeding the UL. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data are from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). ULs from Dietary Reference Intake reports (IOM, 1998, 2001, 2011).

TABLE 4-10 Estimated Prevalence of Inadequacy of Selected Micronutrients Compared to Estimated Average Requirement (EAR) Values, Formula-Fed Infants 6 to Less Than 12 Months of Age, NHANES 2005–2008 and 2011–2012

NOTES: EAR = Estimated Average Requirement; N = sample size; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

^a % Inadequacy = percentage of individuals with usual intake below the EAR.

Subgroup definitions are as follows:

^b WIC = All individuals reporting participation in WIC regardless of income level.

^c Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^d All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data are from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). EARs are from Dietary Reference Intake reports (IOM, 1998, 2001).

TABLE 4-11 Estimated Mean Usual Intakes of Selected Micronutrients Compared to Adequate Intake (AI) Values, Formula-Fed Infants 6 to Less Than 12 Months of Age, NHANES 2005–2008 and 2011–2012

NOTES: αTOC = α-tocopherol equivalents; AI = Adequate Intake; DFE = dietary folate equivalent; N = sample size; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data are from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). AIs are from Dietary Reference Intake reports (IOM, 1997, 1998, 2000, 2001, 2002/2005, 2005, 2011).

TABLE 4-12 Estimated Usual Intakes of Macronutrients, Formula-Fed Infants 6 to Less Than 12 Months of Age, NHANES 2005–2008 and 2011–2012

NOTES: AI = Adequate Intake; EAR = Estimated Average Requirement; g/d = grams per day; g/kg/d = grams per kilogram of body weight per day; kcal = kilocalories; N = sample size; NR = no recommendation; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). Reference intakes for protein, total carbohydrate, and total fat are per the Dietary Reference Intake report (IOM, 2002/2005).

receive 806 fl oz per month (537 kcal per day), and infants 4 to less than 6 months of age receive 884 fl oz per month (589 kcal per day). These quantities of formula provide slightly less energy than the calculated EER for the WIC subgroup in this report, 594 kcal per day. Infants participating in WIC who consume infant formula as their sole source of nutrition would be provided with 8.1 to 8.8 mg of iron per day at this range of energy intakes. This quantity of iron is above the AI (0.27 mg per day), but below the UL (40 mg per day) for infants in this age category (see Table 4-15). In this analysis, WIC formula provided to infants ages 6 to less than 12 months

TABLE 4-13 Estimated Usual Energy Intake and Estimated Energy Requirement, Formula-Fed Infants 6 to Less Than 12 Months of Age, NHANES 2005–2008 and 2011–2012

NOTES: EER = Estimated Energy Requirement; kcal = kilocalories; N = sample size; SE = standard error.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). EERs were calculated according to Dietary Reference Intake report (IOM, 2002/2005).

provides approximately half of energy needs, based on the EER for WICparticipating children, and slightly less than the AI for iron. It is presumed that infants begin to receive complementary foods between 4 and 6 months of age to meet their increased needs for energy and nutrients.

Nutrient Intakes of Children, Ages 1 to Less Than 2 Years

For this age group, there were no statistically significant differences between WIC participants and eligible non-WIC subgroups.

Micronutrient Adequacy

For children 1 to less than 2 years of age, estimated mean usual intakes of all nutrients with EARs were adequate across all subgroups, with the exception of vitamin E (see Table 4-16).

TABLE 4-14 Estimated Prevalence of Micronutrient Excess Compared to the Tolerable Upper Intake Level (UL), Formula-Fed Infants 6 to Less Than 12 Months of Age, NHANES 2005–2008 and 2011–2012

NOTES: N = sample size; SE = standard error; UL = Tolerable Upper Intake Level. Less than 0.01% of all subgroups had folic acid intakes above the UL. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data are from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). ULs are from Dietary Reference Intake reports (IOM, 2000b, 2001, 2011).

Intakes of Nutrients with an AI

Among nutrients with AIs, mean potassium intakes were below the AI for all subgroups (see Table 4-17). Mean intakes of other nutrients fell above the AI values.

Macronutrient and Energy Intake

The macronutrient intakes for this age group are summarized in Table 4-18. Although the 2015 DGAC report’s recommendations were for children aged 2 years and older, the recommended limits on percentage of energy from saturated fat and grams of sugar are applied here as well. Mean saturated fat intakes were high across all subgroups (more than 10 percent of energy), and fiber intakes were low. For WIC participating children, intake of added sugars was approximately twice the recommended

TABLE 4-15 Energy and Iron Provided to Fully Formula-Feeding WIC Infants Compared to the EER and DRI

NOTE: AI = adequate intake; DRI = Dietary Reference Intake; EAR = Estimated Average Requirement; EER = Estimated Energy Requirement; FNB = full nutrition benefit; UL = Tolerable Upper Intake Level.

^a Based on the USDA-FNS final rule.

^b Based on formula-fed infants ages 0 to less than 6 months in NHANES 2005–2008, n = 204. This information has been updated since the initial release of this report.

^c Based on formula-fed infants ages 6 to less than 12 months in NHANES 2005–2008, n = 252.

^d Based on the WIC minimum requirement of 1.5 mg iron/100 kilocalories) at standard dilution.

^e An AI value (mean intakes exceeding this value are likely to be adequate).

^f An EAR value (mean intakes below this value are likely to be inadequate).

SOURCES: USDA/FNS, 2014; NHANES data from USDA/ARS, 2005–2008; EERs were calculated according to Dietary Reference Intake report (IOM, 2002/2005).

limit (3.2 tsp-eq per day) for the 1,000–1,300 kcal weighted diet pattern⁶ applied to children in this report. If a lower energy intake level, closer to the mean EER for WIC participants in this age group was considered (925 kcal), intakes of these macronutrients are of even greater concern. As noted for women who also had low intakes of carbohydrate, the focus for this age group is the excessive intake of saturated fat as opposed to low carbohydrate intake.

Usual energy intake estimates and the corresponding EER values are presented in Table 4-19. Estimated mean intakes exceeded the EERs across subgroups. For example, energy intake of WIC participating children (1,314 kcal per day) was 42 percent higher than the EER for this subgroup (925 kcal per day).

__________________

⁶ To evaluate the diets of all children 1 to less than 5 years of age, the committee applied a weighted food pattern (a 1,000 kcal pattern weighted 1:3 with the average of 1,200- and 1,400-kcal patterns) as described in Chapter 3.

TABLE 4-16 Estimated Prevalence of Inadequacy of Selected Micronutrients Compared to Estimated Average Requirement (EAR) Values, Children 1 to Less Than 2 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: αTOC = α-tocopherol; DFE = dietary folate equivalent; EAR = Estimated Average Requirement; N = sample size; RAE = retinol activity equivalent; SE = standard error. Inadequacy was < 0.15 for copper, zinc, and riboflavin. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

^a % Inadequacy = percentage of individuals with usual intake below the EAR.

Subgroup definitions are as follows:

^b WIC = All individuals reporting participation in WIC regardless of income level.

^c Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^d All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). EARs are from Dietary Reference Intake reports (IOM, 1997, 1998, 2000, 2001, 2002/2005, 2005, 2011).

Micronutrient Excess

Among all subgroups of children ages 1 to less than 2 years of age, the prevalence of nutrient intakes exceeding the UL was more than 5 percent (see Table 4-20) for zinc, selenium, and retinol. Although there was a high prevalence of zinc and retinol intakes above the UL, this is not of concern

TABLE 4-17 Estimated Mean Usual Intakes of Selected Micronutrients with an Adequate Intake (AI) Value, Children 1 to Less Than 2 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: AI = Adequate Intake; N = sample size; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data are from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). AIs are from Dietary Reference Intake reports (IOM, 1998, 2005).

for children ages 1 to less than 2 because of the derivation of these values, as described in Chapter 3. The largest difference in excessive intake between WIC-participating children and WIC-eligible nonparticipating children was for selenium (5 percent in WIC participants, compared to 12 percent in non-WIC participants). Even though apparently large, this difference was not statistically significant. The prevalence of excess sodium intake was 62 to 66 percent for all children in this age category.

Nutrient Intakes of Children, Ages 2 to Less Than 5 Years

Micronutrient Adequacy

For children ages 2 to less than 5 years of age, there was a high prevalence of inadequate intake of calcium and vitamin E across all subgroups (see Table 4-21). There were no statistically significant differences between WIC-participant and eligible non-WIC subgroups.

Intakes of Nutrients with an AI

For nutrients with AIs, mean potassium intakes were below the AI for all subgroups (see Table 4-22), while mean choline intakes appear to be

TABLE 4-18 Estimated Intakes of Macronutrients Compared to Recommended Intakes, Children 1 to Less Than 2 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: AI = Adequate Intake; AMDR = Acceptable Macronutrient Distribution Range; g/d = grams per day; g/kg/d = grams per kilogram of body weight per day; kcal = kilocalories; N = sample size; SE = standard error; tsp-eq/d = teaspoon equivalents per day. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

^a Values represent a DRI except for added sugars and saturated fat, for which values represent the recommended upper limit of daily intake for the 1,300 kcal “weighted” food pattern as described in Chapter 3. The resulting calorie level (1,225) may be slightly high for children in this age group.

Subgroup definitions are as follows:

^b WIC = All individuals reporting participation in WIC regardless of income level.

^c Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^d All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). Reference intakes for protein, total carbohydrate, total fat, and fiber are per the Dietary Reference Intake report (IOM, 2002/2005). Reference intakes for saturated fat and added sugars are per the Scientific Report of the 2015 Dietary Guidelines Advisory Committee (USDA/HHS, 2015).

TABLE 4-19 Estimated Usual Energy Intake and Estimated Energy Requirement, Children 1 to Less Than 2 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: EER = Estimated Energy Requirement; kcal = kilocalories; N = sample size; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). EERs were calculated according to Dietary Reference Intake report (IOM, 2002/2005).

adequate and mean sodium intakes were well above the AI. There were no statistically significant differences between WIC and eligible non-WIC subgroups. As for the other age groups, nutrient intake distributions for this age group are presented in Appendix P.

Macronutrient and Energy Intake

Protein intakes were adequate for all children in this age group, and mean carbohydrate intake fell within the AMDR across all subgroups (see Table 4-23). The prevalence of low total fat intakes ranged from 9 to 15 percent, with the greatest difference between WIC participating children (15 percent) and WIC-eligible nonparticipating children (9 percent). The prevalence of excessive total fat intakes ranged from 6 to 9 percent across the subgroups. Mean saturated fat intakes were only slightly above the recommended 10 percent of energy intakes across all subgroups, although

TABLE 4-20 Estimated Prevalence of Micronutrient Excess Compared to the Tolerable Upper Intake Level (UL), Children 1 to Less Than 2 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: DFE = dietary folate equivalent; N = sample size; SE = standard error; UL = Tolerable Upper Intake Level. Not included in table: percentages above the UL for these nutrients were < 0.01 percent: copper, iron, phosphorus, vitamin B6, folic acid, and choline. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals that did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data are from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). ULs are from Dietary Reference Intake reports (IOM, 1997, 1998, 2000, 2001, 2002/2005, 2005, 2011).

as noted in the next paragraph, reported energy intake appeared to be excessive. Fiber intakes were approximately half the AI. Mean added sugars intakes (15 tsp-eq per day; see Appendix P) were approximately five-fold of the recommended limit for a weighted 1,300 kcal diet.

Usual mean energy intakes and the corresponding EER values are presented in Table 4-24. As for younger children, reported energy intakes exceeded the calculated EERs for all subgroups, although the difference among the subgroups was smaller than it was for the younger children. Among WIC-participating children, mean energy intakes (1,534 kcal per day) were approximately 18 percent higher than the predicted requirements (1,295 kcal per day). There were no statistically significant differences between WIC and eligible non-WIC subgroups.

TABLE 4-21 Estimated Prevalence of Inadequacy of Selected Nutrients Compared to the Estimated Average Requirement (EAR) Value, Children 2 to Less Than 5 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: αTOC = α-tocopherol; DFE = dietary folate equivalent; EAR = Estimated Average Requirement; N = sample size; RAE = retinol activity equivalent; SE = standard error. Inadequacy across all subgroups was < 0.01 for iron, selenium, riboflavin, folate, and vitamin B12. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

^a % Inadequacy = percentage of individuals with usual intake below the EAR.

^b The approach of IOM (2000) was applied in which, when combining groups with different EARs, intakes in one of the groups are rescaled so they can be compared to the EAR of the other group.

Subgroup definitions are as follows:

^c WIC = All individuals reporting participation in WIC regardless of income level.

^d Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^e All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). EARs are from Dietary Reference Intake reports (IOM, 1997, 1998, 2000, 2001, 2002/2005, 2005, 2011).

TABLE 4-22 Estimated Mean Usual Intakes of Selected Micronutrients Compared to the Adequate Intake (AI) Value, Children 2 to Less Than 5 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: AI = Adequate Intake; N = sample size; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). AIs are from Dietary Reference Intake reports (IOM, 1998, 2005).

Micronutrient Excess

For a number of micronutrients, more than 5 percent of children in this age category exceeded the UL across all subgroups: copper, zinc, sodium, and retinol (see Table 4-25). For most micronutrients consumed in excess, WIC-participating children and WIC-eligible nonparticipating subgroups had similar proportions of excess intake. The largest difference was for zinc, with 54 percent of WIC participants exceeding the UL, compared to 45 percent of nonparticipants, a statistically significant difference (p < 0.05). The highest prevalence of excess intake was for sodium (up to 91 percent).

Special Case: Vitamin D Status Across Age Categories

Vitamin D Status

As explained in Chapter 3, serum 25(OH)D concentrations are considered a more accurate indicator of vitamin D status than dietary intake because an individual’s vitamin D status is determined by both dietary intake and sun exposure. Thus, instead of relying on dietary intake, serum

TABLE 4-23 Estimated Intakes of Macronutrients Compared to Recommended Intakes, Children 2 to Less Than 5 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: AI = Adequate Intake; AMDR = Acceptable Macronutrient Distribution Range; DRI = Dietary Reference Intake; g/d = grams per day; g/kg/d = grams per kilogram of body weight per day; kcal = kilocalories; N = sample size; tsp-eq/d = teaspoon equivalents per day. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

^a Values represent a DRI except for added sugars and saturated fat, for which values represent the recommended upper limit of daily intake for the 1,300 kcal “weighted” food pattern as described in Chapter 3. The resulting calorie level (1,225) may be low for children in this age group.

^b Where two values are presented, the approach of IOM (2000) was applied in which, when combining groups with different DRIs, intakes in one of the groups are rescaled so they can be compared to the DRI of the other group.

Subgroup definitions are as follows:

^c WIC = All individuals reporting participation in WIC regardless of income level.

^d Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^e All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). Reference intakes for protein, total carbohydrate, total fat, and fiber are per Dietary Reference Intake report (IOM, 2002/2005). Reference intakes for saturated fat and added sugars are per the Scientific Report of the 2015 Dietary Guidelines Advisory Committee (USDA/HHS, 2015).

TABLE 4-24 Estimated Usual Energy Intake and Estimated Energy Requirement, Children 2 to Less Than 5 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: EER = Estimated Energy Requirement; kcal = kilocalories; N = sample size; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

SOURCES: Intake data were obtained from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). EERs were calculated according to Dietary Reference Intake report assuming a low-active physical activity level (IOM, 2002/2005).

25(OH)D concentrations were analyzed to assess vitamin D status among all subgroups and across all age categories. The serum distributions presented in Table 4-26 indicate a low prevalence of inadequacy (no more than 5 percent) for the subgroups of children when compared to the serum value that is linked to the EAR, 40 nmol/L (IOM, 2011). However, the prevalence of inadequacy was undesirably high (21 percent) among pregnant, breastfeeding, and postpartum women. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Vitamin D Intakes

Infants less than 12 months of age Dietary vitamin D intakes of infants are presented in Table 4-27 because serum vitamin D data are not available for this age group. The AI for vitamin D in this age group is 10 μg per day. As described in Chapter 3, however, these values establish baseline vitamin D

TABLE 4-25 Estimated Prevalence of Micronutrient Excess Compared to the Upper Tolerable Intake Level (UL), Children 2 to Less Than 5 Years of Age, NHANES 2005–2008 and 2011–2012

NOTES: DFE = dietary folate equivalent; N = sample size; SE = standard error; UL = Tolerable Upper Intake Level. Not included in table: percentages above the UL for these nutrients were < 0.01 percent: iron, phosphorus, vitamin B6, folic acid, and choline.

^a The approach of IOM (2000) was applied in which, when combining groups with different EARs, intakes in one of the groups are rescaled so they can be compared to the EAR of the other group.

Subgroup definitions are as follows:

^b WIC = All individuals reporting participation in WIC regardless of income level.

^c Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^d All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

^e Significantly different from eligible non-WIC participants (p < 0.05) by t-test.

SOURCES: Intake data are from NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012). ULs are from Dietary Reference Intake reports (IOM, 1997, 1998, 2000, 2001, 2002/2005, 2005, 2011).

intake to use for the assessment of the effect of potential food package changes on intakes of this nutrient and provide little information about the vitamin D adequacy of infants.

Other age groups relevant to the WIC food packages As described in Chapter 3, dietary intake of vitamin D is not well correlated with status of this nutrient. Vitamin D intakes of other relevant WIC subgroups will be presented in the phase II report to evaluate the potential effect of food package modifications on intake of vitamin D.

TABLE 4-26 Distributions of Serum 25-Hydroxy Vitamin D, NHANES 2005–2006^a

NOTES: 25(OH)D = 25-hydroxy vitamin D; N = sample size; P/BF/PP = pregnant, breastfeeding, or postpartum; SE = standard error. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

^a Serum data for 25-hydroxy vitamin D are only available in NHANES 2005–2006.

Subgroup definitions are as follows:

^b WIC = All individuals reporting participation in WIC regardless of income level.

^c Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^d All Low-Income = All individuals at ≤ 185 percent of poverty. At the time of analysis, the WIC indicator was not available for NHANES 2011–2012. Thus, the “All Low-Income 2011–2012” group serves as a proxy for current intakes of this population.

^e Some women reporting WIC participation did not report being pregnant, breastfeeding, or postpartum.

^f A serum 25(OH)D level of 40 nmol/L was established by IOM (2011) as an average requirement that meets the needs of approximately half the population, used to establish EARs for dietary intake of vitamin D.

SOURCES: NHANES 2005–2006 (USDA/ARS, 2005–2006).

TABLE 4-27 Mean Vitamin D Intakes of Formula-Fed Infants Less Than 12 Months, NHANES 2007–2008 and 2011–2012

NOTES: AI = Adequate Intake; N = sample size; SE = standard error. Vitamin D intake was not reported in 2005–2006 for this age group. There were no statistically significant differences between WIC and eligible non-WIC subgroups.

Subgroup definitions:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty.

SOURCES: Intake data are from NHANES 2007–2008 and 2011–2012 (USDA/ARS, 2007–2008, 2011–2012). AIs from Dietary Reference Intake report (IOM, 2011).

Special Case: Vitamin E

As was the case with the subgroups included in the committee’s NHANES analyses, low vitamin E intake appears to be ubiquitous in the general U.S. population. However, because clinical vitamin E deficiency is uncommon (IOM, 2000), neither the 2015 DGAC report nor the 2010 DGA considered it to be a nutrient of public health concern (USDA/HHS, 2010, 2015). Given the high prevalence of vitamin E inadequacy identified in this analysis, the committee sees vitamin E intake as requiring further attention.

EVALUATION OF DIET QUALITY

Two indexes of diet quality were applied to all three NHANES subgroups and across all age groups: (1) the Healthy Eating Index-2010 (HEI-2010), as requested by USDA-FNS (results are presented in Chapter 5), and (2) a nutrient-based diet quality (NBDQ) index, which was created by the committee. The NBDQ index has a maximum score of 100 and is based on the probability of adequacy of the shortfall nutrients, as defined by the 2015 DGAC report (see details of the methodology in Appendix K, document K-1). The NBDQ values for women, children 1 to less than 2 years of age, and children 2 to less than 5 years of age, are presented in Tables 4-28

TABLE 4-28 NBDQ Index Distributions for Pregnant, Postpartum, or Breastfeeding Women, 19 to 50 Years of Age

NOTES: N = number of observations; NBDQ = Nutrient-Based Diet Quality index designed by the committee. Numbers represent probability of adequacy for the nine shortfall nutrients outlined in the Scientific Report of the 2015 Dietary Guidelines Advisory Committee (potassium; calcium; iron; vitamins A, E, and C; folate; magnesium; and fiber; iron for adolescent and premenopausal females) (USDA/HHS, 2015).

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level. Some women reporting WIC participation did not report being pregnant, breastfeeding, or postpartum.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty.

SOURCES: NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012).

TABLE 4-29 NBDQ Index Distributions for Children, 1 to Less Than 2 Years of Age

NOTES: N = number of observations; NBDQ = Nutrient-Based Diet Quality index designed by the committee. Numbers represent probability of adequacy for the nine shortfall nutrients outlined in the Scientific Report of the 2015 Dietary Guidelines Advisory Committee (potassium; calcium; iron; vitamins A, E, and C; folate; magnesium; and fiber; iron for adolescent and premenopausal females) (USDA/HHS, 2015).

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty.

SOURCES: NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012).

TABLE 4-30 NBDQ Index Distributions for Children, 2 to Less Than 5 Years of Age

NOTES: N = number of observations; NBDQ = Nutrient-Based Diet Quality index designed by the committee. Numbers represent probability of adequacy for the nine shortfall nutrients outlined in the Scientific Report of the 2015 Dietary Guidelines Advisory Committee (potassium; calcium; iron; vitamins A, E, and C; folate; magnesium; and fiber; iron for adolescent and premenopausal females) (USDA/HHS, 2015).

Subgroup definitions are as follows:

^a WIC = All individuals reporting participation in WIC regardless of income level.

^b Eligible Non-WIC = Low-income individuals who did not report participation in WIC.

^c All Low-Income = All individuals at ≤ 185 percent of poverty.

SOURCES: NHANES 2005–2008 and 2011–2012 (USDA/ARS, 2005–2008, 2011–2012).

through 4-30. The NBDQ could not be calculated for infants because there are so few nutrient EARs for the two infant age groups. Mean scores on the NBDQ were lower for women (48–50) than for children (64–69); this indicates that women were more likely than children to have inadequate intakes of the shortfall nutrients. Within population subgroups, mean scores were similar for WIC participants and nonparticipants.

CONSIDERATIONS FOR DATA INTERPRETATION

The analyses described in this chapter were designed to address the committee’s task as closely as possible given what was available at the time the analyses were conducted. Although the accuracy of data reported in NHANES has been questioned (Archer et al., 2013), it remains the best available source of nationally representative food and nutrient intake data. In their recent commentary, Subar et al. (2015) provide a detailed review of the strengths and limitations of the NHANES data. They acknowledge the weakness of NHANES for some purposes but also note the utility of these data for developing population-level policies related to nutrition. Nonetheless, use of NHANES data had limitations relative to the committee’s task, as previously noted in the Letter Report issued for this study (IOM, 2015).

First, the WIC to non-WIC comparisons were made using data from 2005–2008, which were not the most recent NHANES datasets available. Although these analyses update the prior Institute of Medicine (IOM) report (2006), a more recent and WIC-focused comparison (using NHANES 2011–2012) is desirable. The indicator of WIC participation was not available for the most recent NHANES dataset in time for this report, but it will be available for phase II.

Second, using NHANES data to capture data from WIC participants specifically depends on accurate self-identification by WIC recipients in NHANES, and determination of “eligibility” among other, low-income individuals. The committee’s comparison of the weighted total number of recipients reporting WIC participation, as well as extensive experience reporting on social assistance programs like WIC, suggest that WIC use is underreported in NHANES (Bitler et al., 2003; Celhay et al., 2015; Meyer et al., 2015). In addition, there are challenges to determining individuals who are “eligible” but do not participate accurately. In addition to determination of demographic or physiological eligibility (i.e., age, pregnancy, postpartum, and breastfeeding status), some WIC-eligible individuals may not be captured in the NHANES low-income (≤ 185 percent poverty-to-income ratio [PIR]) groups because they are of higher income levels. Applying the income criterion of ≤ 185 percent of the PIR does not necessarily correspond to state-level income requirements for WIC eligibility. Individuals may still legitimately participate in the program if adjunctively or automatically eligible due to participation in Medicaid, Temporary Assistance for Needy Families (TANF), or the Supplemental Nutrition Assistance Program (SNAP). For these reasons, there may be more individuals eligible for WIC than would be included in a screen of ≤ 185 percent of the PIR. Finally, even if NHANES were to capture WIC participation exactly, the number of participants who are enrolled in WIC would still be very small.

Estimating Micronutrient Adequacy

To estimate the adequacy of micronutrient intake, adjustments were made to calculate nutrient adequacy in analytical subgroups in which more than one EAR was applicable. Using this method may conceal a relatively high prevalence among pregnant women and a much lower prevalence among lactating women, as described in Chapter 3. This case is applicable to the assessment of iron adequacy in children and iron and folate adequacy in women. In addition, iron inadequacy in women may be incorrectly estimated because a normal distribution of requirements was used, which assumes that women who are pregnant, lactating, or postpartum do not skew requirements due to menstrual losses. As noted previously, for nutrients with an AI value only, no inference can be made about nutrient adequacy.

Several of the micronutrient intake estimates should be interpreted with caution because of small sample sizes (see Chapter 3, Table 3-2). The committee calculated that a mean usual nutrient intake can be calculated within 3 percent of the true value (95 percent confidence interval) with a minimum of 18–20 individuals, depending on nutrient and on age group. This minimum may not apply to calculation of population-level intake adequacy. At the same time, the statistical method applied gives relatively reliable numbers around the median and mean even with small sample sizes, but with less reliability at the tails of distributions. Sample sizes for women remained small despite combining all pregnant, breastfeeding, and postpartum individuals, but the estimates were stabilized by weighting the external variance, and therefore, should be reliable (Jahns et al., 2005).

Finally, because all women were combined to generate more robust sample sizes, it was not possible to determine differences in the prevalence of inadequacy among these three reproductive categories. Furthermore, mean intakes and prevalences of inadequacies for these subpopulations may be affected by differing proportions of pregnant, lactating, and postpartum women within each subpopulation. As a result, comparison across the subpopulations (such as WIC versus WIC-eligible) should be interpreted with extra caution.

Estimating Macronutrient and Energy Intake

Although the EERs have been published, an individual’s requirements depend on many factors and cannot be precisely estimated. The EERs used in this report were calculated based on established equations developed by the IOM (2002/2005). Recently, Butte et al. (2014) proposed that the IOM (2002/2005) equations overestimate energy expenditure for toddlers because they are based on incorrect physical activity assumptions. The

committee is aware of this finding and will consider it when developing its final recommendations.

The mean energy intake of infants was at least 30 percent higher than the EER used in this report and, for children, 42 percent (children 1 to less than 2 years) and 18 percent (children 2 to less than 5 years) higher. This suggests that caretakers of children in these subgroups may be over-reporting energy intakes, as has been proposed in other studies (Eck et al., 1989; Devaney et al., 2004) as well as in the previous IOM review of WIC food packages (IOM, 2006). Assessing dietary intake in people of any age is challenging, but measuring the diet of infants and very young children can be particularly problematic. Multiple people may be responsible for the care of the child, and collecting an accurate picture of intake often requires combining parental reports with observations from other caretakers (Foster and Adamson, 2014). Should over-reporting be the case, nutrients identified in the NHANES analyses as under-consumed become more significant concerns.

In contrast to infants and children, reported mean energy intakes of women in this report were 10 percent lower than estimated average needs. There is robust evidence that adults tend to underreport energy intakes if they are overweight (Macdiarmid and Blundell, 1998), and the Centers for Disease Control and Prevention data indicate higher levels of obesity in lower-income women (CDC, 2010). A recent evaluation of reporting accuracy in NHANES 2002–2012 indicated that 25 percent of adults ages 20 and older were likely to underreport energy intake. Respondents were more likely to underreport if female, non-Hispanic black, having lower education or income, and if overweight or obese (Murakami and Livingstone, 2015). Archer et al. (2013) and Subar et al. (2015) agree that self-reported energy intake is of limited value as a measure of true energy intake. Under-reporting could exaggerate the estimated micronutrient inadequacies for women identified in this report, however, as noted in Subar et al. (2015), if the discrepancy between reported and recommended intakes is large enough, concern may be warranted even considering a degree of error. In general, underreporting is more pervasive than over-reporting (Murakami and Livingstone, 2015), especially among overweight and obese women (Briefel et al. 1995; McKenzie et al., 2002).

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