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Nutrition Provided to Mexican-American Preschool Children on the Texas–Mexico Border
RESEARCH Research and Professional Briefs
Nutrition Provided to Mexican-American Preschool Children on the Texas–Mexico Border NELDA MIER, PhD; VERONICA PIZIAK, MD, PhD; DEAN KJAR, MS; OCTELINA CASTILLO-RUIZ, MPH; GONZALO VELAZQUEZ, PhD; MARIA E. ALFARO; JOSE A. RAMIREZ, PhD
ABSTRACT The purpose of this study was to assess whether nutrients offered to border Mexican-American preschool children met the Recommended Dietary Allowances. Nutrient contents of two dietary patterns were examined in this study, one composed exclusively of home foods and one containing a combination of both home and school foods. The sample consisted of 198 Mexican-American preschoolers living on the Texas–Mexico border, who were recruited using a convenience sampling technique. A self-administered, precoded 24-hour recall questionnaire was used. Nutrient values of home foods were collected during a weekend day, and nutrient values containing a combination of both home and school foods were collected during a weekday. Fisher’s exact test or 2 test and t test were used for analyses. Mean nutrient contents of foods provided to the border Mexican-American children exceeded recommendations for total energy (P⬍0.001), total fat (P⬍0.001), saturated fat (P⬍0.001), carbohydrates (P⬍0.001), protein (P⬍0.001), sodium (P⬍0.001), and niacin (P⬍0.001). Foods offered were also significantly insufficient in fiber (P⬍0.001), vitamin A (P⬍0.001), and potassium (P⬍0.001). Nutrition interventions targeting low-income border Mexican-American families should emphasize the need and importance of
N. Mier is assistant professor in Social and Behavioral Health at the South Texas Center School of Rural Public Health, Health Science Center, Texas A&M University System, McAllen. V. Piziak is chief of Endocrinology and professor of Medicine at the Health Science Center, Texas A&M University System, Temple. D. Kjar is a biostatistician at Scott & White, Temple, TX. O. Castillo-Ruiz is professor in Nutrition, G. Velazquez is chief of Food and Technology, M.E. Alfaro is a college graduate in Nutrition, and J. A. Ramirez is director of Graduate Studies, Tamaulipas Autonomous University Reynosa-Aztlan Campus, Reynosa, Mexico. Address correspondence to: Nelda Mier, PhD, South Texas Center School of Rural Public Health, Health Science Center, Texas A&M University System, 2101 South McColl Rd, Room 134, McAllen, TX 78503. E-mail: [email protected] Copyright © 2007 by the American Dietetic Association. 0002-8223/07/10702-0006$32.00/0 doi: 10.1016/j.jada.2006.11.013
© 2007 by the American Dietetic Association
providing children with diets that meet the Recommended Dietary Allowances. J Am Diet Assoc. 2007;107:311-315.
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reschool children from underserved minority groups are at high risk of both obesity and malnutrition because of eating habits that do not meet the Dietary Guidelines for Americans (1,2). In particular, MexicanAmerican preschool children are at higher risk of becoming obese than white non-Hispanic children (2-4). Data from National Health and Nutrition Examination Surveys between 1999 and 2004 indicate that the prevalence of overweight (body mass index for age ⱖ95 percentile) among Mexican-American children 2 to 5 years of age increased from 10.9% to 19.2% (3). Several other studies found that young Mexican-American children are twice as likely to be overweight or at risk of overweight than non-Hispanic white, black, and Asian children (3,5-7). Prevalence data collected in the Texas–Mexico border region show that 18.1% of 2,376 Mexican-American preschool children were obese (body mass index for age ⱖ97 percentile) (8,9). Part of the increase in childhood obesity can be explained by parental child-feeding practices. Studies show that when parents consume a high-energy-dense diet, children are more likely to have a similar diet (10,11). Children’s food preferences have also been associated with parental influence (10-16). Notwithstanding the considerable research assessing what is offered to and consumed by school-aged children in elementary to high school grades (17-20), there is scarce research examining the adequacy of nutrient contents of foods offered in a combined home and school setting to Mexican-American preschoolers living in the United States–Mexico border region. Nutrition research focusing on the border region is of great importance. Forty-nine percent of the border population is primarily of Mexican ancestry (21). This population is medically underserved and poor (21-24), and about 75% of adults are either overweight or obese (25). Moreover, almost 16% of border residents suffer from type 2 diabetes, a rate higher than the national rate in Mexico (14.9%) and the United States (13.9%) (25). The purpose of this study was to determine if nutrients offered to border Mexican-American preschool children met the Recommended Dietary Allowances. Nutrient contents of two dietary patterns were compared with recommendations (26,27), one composed exclusively of home foods and one containing a combination of home and
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school foods. We hypothesized that Mexican-American preschool children living at the border have diets offered at home and at a combined home and school setting that exceed recommendations for total energy and most macronutrients. METHODS Participants and Setting Participants were Mexican-American children 3 to 5 years of age attending two full-day Head Start centers in the easternmost area of the Texas–Mexico border region. In this region, a majority of the population is of Mexican descent (87%), and Spanish is spoken in three quarters of homes. Also, this population is young (38% under age 19) compared with state (31%) and national (29%) populations. In addition, two thirds of individuals under 25 years of age have less than a ninth-grade education. Access to medical care is limited and the major metropolitan areas in the region rank last in the nation in per capita income (24,28). Although 232 children were eligible to participate, this study included data from 198 children for whom there were no missing data. Participants were recruited using a convenience sampling technique and a majority were male (55%). Data were collected in 2003. This study received approval from the Institutional Review Board of Scott & White* and the Texas A&M University System, and informed consent was obtained from parents. Study Design and Measurement Parents of the children were asked to report the foods they offered to their child during a weekend day and a weekday. Parental information was obtained using a selfadministered precoded 24-hour recall that reflected foods offered to young Mexican Americans in the Texas–Mexico border area. A precoded food list was developed for this study by the researchers, based on feedback from Head Start staff as well as the Head Start daily menu. The precoded 24-hour recall was administered to 13 parents to test for readability, appropriateness of food list, and general ease of survey administration. This type of instrument was used because it is brief, inexpensive, and easily administered. Although the instrument used in the current study has not been validated, previous studies indicate that self-administered precoded 24-hour food recalls are a valid method to assess diets of young children (29-33). In addition, single-day dietary data are adequate for comparisons of groups if the sample sizes are sufficiently large (34,35). Nine teachers were trained to provide parents a detailed explanation of the study purpose and methods. Questionnaires were handed out in class and children were asked to take them home to their parents for completion. The questionnaire elicited information from parents about yesterday’s foods offered to their child for 1
*Scott & White is an institution that combines a clinic, hospital, and health plan and serves Central Texans. Scott & White’s main facilities are located in Temple, TX.
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weekday and 1 weekend day. The questionnaire was in English or Spanish and met literacy levels of participants. Weekday data also included foods offered to the children through the daily Head Start menu. For analysis purposes, we created two categories: the “home diet” and the “school plus home diet.” The home diet included data obtained from the parents describing foods offered to the children exclusively at home during a weekend day. The school-plus-home diet computed nutrient values obtained from both parental reports and foods listed on the daily menu served by Head Start on the weekday reported by the parents. The school menu offered two meals and snacks to children and met two thirds of recommendations (36). In addition, this study was based on values from the Dietary Reference Intakes for the 4- to 8-year-old age group (26) and the National Cholesterol Education Program guidelines (27) to compare diets and recommendations. Statistical Analyses Nutrient contents of dietary patterns were averaged and compared to recommendations. Nutrient values were computed using NutriPac (NutriPac, v1.5, 1992-2003, Mexico City, Mexico), which is software that includes food-composition data appropriate for food intake of our population. Mean energy, macronutrients, and selected micronutrient contents of foods were analyzed (total energy, total fat, saturated fat, cholesterol, protein, carbohydrate, saturated fat, fiber, calcium, iron, magnesium, zinc, potassium, sodium, vitamin A, C, thiamin, riboflavin, B-6, B-12, niacin, and folate). Differences in nutrient contents between diets were analyzed using 2 test or Fisher’s exact test. A t test was used to compare nutrient contents of dietary patterns with recommendations. The SAS software program (SAS Institute Inc, v8.2, 1999, Cary, NC) was used to conduct statistical analyses. A P value ⬍0.05 was considered significant for all statistical tests conducted. RESULTS AND DISCUSSION The Table details mean contents of micronutrients, vitamins, and minerals of each dietary pattern in comparison with the Recommended Dietary Allowances. Dietary patterns exceeded recommendations for some of the macronutrients. The mean value of total energy in both dietary patterns significantly exceeded (1.5 times) recommendations (P⬍0.01). Total fat and saturated fat were almost double the recommendations (P⬍0.01). Considering that the acceptable upper limit amount for carbohydrates is 227 g (65% of the caloric intake) based on recommendations for children in this age group (not shown in the table), the mean value of carbohydrate content significantly exceeded the upper limit recommendations by almost 60% (P⬍0.001) in both dietary patterns. The mean value of protein exceeded by almost five times (P⬍0.001) the recommended amount in both diets. In addition, the mean value of fiber was significantly below the recommended level by almost 50% (P⬍0.001). Mean values of both dietary patterns met recommendations for most vitamins, except vitamin A. Only one quarter of the children were offered the recommended
Table. Mean amounts of nutrients categorized by dietary pattern offered to Mexican-American preschool children on the Texas–Mexico border and compared to recommendations Nutrient
Home diet (nⴝ106)
School-plus-home diet (nⴝ92)
Energy (kcal) Total fat (g) Saturated fat (g) Kcal from fat Kcal from carbohydrates Carbohydrates (g)e Protein (g)e Fiber (g)e Cholesterol (mg) Vitamin A (g RAEg)e Vitamin C (mg) Thiamin (mg)e Riboflavin (mg)e Niacin (mg) Vitamin B-6 (mg) Folate (g DFEh) Vitamin B-12 (g)e Calcium (mg)e Iron (mg) Magnesium (mg) Zinc (mg) Potassium (mg) Sodium (mg)
4™™™™™™™™™™™™™™™™™ mean⫾SD b ™™™™™™™™™™™™™™™ 3 2,353⫾1,045cx 2,623⫾901dx 67.9⫾38.4cx 81.2⫾31.4dx 24.1⫾14.0cx 33.1⫾13.3dx cx 611.1⫾345.6 730.8⫾282.6dx 1,452⫾692cx 1,520⫾628dz cx 363⫾173 380⫾157dx 79.3⫾40.9cx 102.3⫾33.7cx 9.0⫾5.2cx 12.1⫾4.7cx 342⫾241c 312⫾197c cx 292⫾206 325⫾232cy 44⫾52cx 41⫾50cy cx 1.4⫾0.8 1.7⫾0.8dx 1.8⫾1.0cx 2.6⫾1.2dx cx 16.5⫾10.2 18.1⫾7.6dx 1.1⫾0.6cx 1.4⫾0.6dx cz 355⫾264dx 263⫾296 6.2⫾7.7cx 8.0⫾7.4dx cy 1,015⫾602 1,692⫾589dx 17.1⫾12.0cx 29.0⫾11.6dx cx 218⫾136 365⫾136dx 7.6⫾4.4cx 10.6⫾3.5dx 2,454⫾159cx 3,451⫾1,558c 2,488⫾1,444cx 2,301⫾1,125cy
Recommendationsa 1,400 46 15.5 414 520 130 19 25 ⬍300f 400 25 0.6 0.6 8 0.6 200 1.2 800 10 130 5 3,800 1,200
a
Represents Recommended Dietary Allowances determined by the Institute of Medicine for the 4- to 8-year-old age group. SD⫽standard deviation. Mean values by type of diet with the same superscript do not differ significantly (P⬎0.05). e Fisher exact test was used instead of 2 test to establish significant differences between diets. f This value is the acceptable level determined by the National Cholesterol Education Program for children over 2 years of age. g RAE⫽retinol activity equivalents. h DFE⫽dietary folate equivalent. x Statistically significant difference between mean and recommendations at P⬍0.001. y Statistically significant difference between mean and recommendations at P⬍0.01. z Statistically significant difference between mean and recommendations at P⬍0.05. b
cd
level of vitamin A in both dietary patterns (not shown in the Table). The Table shows that the home diet met approximately two-thirds of the recommended level of vitamin A (P⬍0.001). The school plus home diet met 80% of the recommended value of vitamin A (P⬍0.01). Although the mean contents of both dietary patterns exceeded recommendations for vitamin C as shown in the Table, half of the participants (n⫽50 in the home diet and n⫽48 in the school plus home diet) were not offered the recommended levels of vitamin C (not shown in the Table). Both home diet and the school-plus-home diet met recommendations for calcium, iron, magnesium, and zinc, but failed recommendations for potassium and exceeded recommendations for sodium. Children’s foods contained more than 1.5 times the recommendations for sodium in both the home diet (P⬍0.001) and the school-plus-home diet (P⬍0.01). In summary, Mexican-American border preschool children in this study were provided with nutrient contents from home foods during a weekend day and from a com-
bination of both home and school foods during a weekday that exceeded considerably the recommendations for several nutrients, including total energy, total fat, saturated fat, carbohydrates, protein, sodium, and niacin. Food contents were significantly insufficient in fiber, vitamin A, and potassium. Consistent with a study by Acosta and colleagues (37), this research found that mean energy of foods offered to Mexican-American children exceeded recommendations. In addition, the present findings indicating mean protein contents exceeding recommendations were consistent with previous studies (37-39). However, while previous studies found that calcium intake among preschool Mexican-American children did not meet recommendations, the present study found an adequate level of calcium offered to a majority of participants. Discrepancy across studies might be related to differences in dietary measurements used. All studies mentioned used modified 24-hour recalls by parental report, and only one (39) also included an observational method. Another possible explanation might be regional and socioenvironmental fac-
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tors influencing feeding practices of Mexican-American children living on the border. Thus, discrepancy across studies warrants additional examination. Although our study found that mean fat contents of foods provided to our cohort exceeded recommendations, the percentage of energy intake from fat (25% in the home diet and 27% in the school-plus-home diet) did not exceed recommendations (30%) (40). Also, results indicate that the children’s diet exceeded recommendations for carbohydrates and protein, but was significantly insufficient in fiber. These findings indicate that border Mexican-American children were offered diets rich in processed and sugary foods and composed of large portions. This study also indicates that a majority of the children were offered dietary patterns deficient in vitamin A. A low consumption of vitamin A among border MexicanAmerican children should be addressed as a potential health risk related to respiratory infection, impaired wound healing, and vision complications (41,42). Although the findings in our study showing that vitamin A was below recommendations are supported by Looker and colleagues (43,44) and Larson and colleagues (38), our results differ from other researchers (37,45), who found an adequate intake of this vitamin. Results from our study showing a deficiency in both vitamin A and C reflect a diet insufficient in fruits and vegetables. This study has several limitations. Because of the convenience sampling technique used, findings of this study can only be generalized to Mexican-American children living at the Texas–Mexico border from poor families that speak Spanish at home, have low education levels, and have insufficient access to health care. Additional research is needed to verify these findings in a larger randomized sample of Mexican-American children along the border. Another limitation was the self-report instrument used. Although this tool was used to estimate nutrients of foods, it did not measure actual intake by direct observation. Also, validity and reliability were not assessed. Finally, it is difficult to code mixed dishes with this instrument (30). Limitations related to the instrument could have led to some inaccuracies in nutrient estimation. CONCLUSIONS Consumption of diets high in energy (compared with needs for growth and physical activity) can put border Mexican-American preschool children at risk of obesity. Nutrition interventions targeting low-income border Mexican-American families should emphasize the need and importance of providing children with diets that meet recommendations. References 1. Bronner YL. Nutritional status outcomes for children: Ethnic, cultural, and environmental contexts. J Am Diet Assoc. 1996;96:891-903. 2. Strauss RS, Pollack HA. Epidemic increase in childhood overweight, 1986-1998. J Am Med Assoc. 2001; 286:2845-2848. 3. Ogden CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM. Prevalence of overweight and obesity in the United States. JAMA. 2006;295: 1549-1555.
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4. Mei Z, Scanlon KS, Grummer-Strawn LM, Freedman DS, Yip R, Trowbridge FL. Increasing prevalence of overweight among US low-income preschool children: The Centers for Disease Control and Prevention pediatric nutrition surveillance, 1983 to 1995. Pediatrics. 1998;101:E12. 5. Stolley MR, Fitzgibbon ML, Dyer A, Van Horn L, KauferChristoffel K, Schiffer L. Hip-Hop to Health Jr., an obesity prevention program for minority preschool children: Baseline characteristics of participants. Prev Med. 2003;36:320-329. 6. Park MK, Menard SW, Schoolfield J. Prevalence of overweight in a triethnic pediatric population of San Antonio, Texas. Int J Obes. 2001;25:409-416. 7. Nelson JA, Chiasson MA, Ford V. Childhood overweight in a New York City WIC population. Am J Public Health. 2004;94:458-462. 8. Mier N, Piziak V. Development of a nutrition demonstration program for Hispanic preschool children living along the United States-Mexico border. Paper presented at the Border Health Association 62nd Annual Meeting. Abstract No. 12. June 10, 2004, Juarez, Mexico. 9. Piziak V. Worldwide childhood obesity. Paper presented at Binational Health Week Forum. Epidemic of Childhood Obesity; October 10, 2004, McAllen, TX. 10. Oliveria SA, Ellision RC, Moore LL, Gillman MW, Garrahie EJ, Singer MR. Parent-child relationships in nutrient intake: The Framingham Children’s Study. Am J Clin Nutr. 1992;56:593-598. 11. Anderson PM, Butcher KF. Childhood obesity: Trends and potential causes. Future Child. 2006;16:19-45. 12. Melgar-Quiñonez HR, Kaiser LL. Relationship of child-feeding practices to overweight in low-income Mexican-American preschool-aged children. J Am Diet Assoc. 2004;104:1110-1119. 13. Faith MS, Keller KL, Johnson SL, Pietrobelli A, Matz PE, Must S, Jorge MA, Cooperberg J, Heymsfield SB, Allison DB. Familial aggregation of energy intake in children. Am J Clin Nutr. 2004;79:844-850. 14. Klesges RC, Stein RJ, Eck LH, Isbell TR, Klesges LM. Parental influence on food selection in young children and its relationships to childhood obesity. Am J Clin Nutr. 1991;53:859-864. 15. Birch LL, Davison KK. Family environmental factors influencing the developing behavioral controls of food intake and childhood overweight. Pediatr Clin North Am. 2001;48:893-907. 16. Hodges EA. A primer on early childhood obesity and parental influence. Pediatr Nurs. 2003;29:13-16. 17. Jimenez-Cruz A, Bacardi-Gascon M, Jones EG. Consumption of fruits, vegetables, soft drinks, and highfat-containing snacks among Mexican children on the Mexico-U.S. border. Arch Med Res. 2002;33:74-80. 18. Jiménez-Cruz A, Bacardí-Gascón M, Spindler AA. Obesity and hunger among Mexican-Indian migrant children on the US-Mexico border. Int J Obes Relat Metab Disord. 2003;27:740-747. 19. Novotny R, Boushey C, Bock MA, Peck L, Auld G, Bruhn CM, Gustafson D, Gabel K, Jenson JK, Misner S, Read M. Calcium intake of Asian, Hispanic and white youth. J Am Coll Nutr. 2003;22:64-70. 20. McKenzie J, Dixon LB, Smiciklas-Wright H, Mitchell
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Nutrition Provided to Mexican-American Preschool Children on the Texas–Mexico Border NELDA MIER, PhD; VERONICA PIZIAK, MD, PhD; DEAN KJAR, MS; OCTELINA CASTILLO-RUIZ, MPH; GONZALO VELAZQUEZ, PhD; MARIA E. ALFARO; JOSE A. RAMIREZ, PhD
ABSTRACT The purpose of this study was to assess whether nutrients offered to border Mexican-American preschool children met the Recommended Dietary Allowances. Nutrient contents of two dietary patterns were examined in this study, one composed exclusively of home foods and one containing a combination of both home and school foods. The sample consisted of 198 Mexican-American preschoolers living on the Texas–Mexico border, who were recruited using a convenience sampling technique. A self-administered, precoded 24-hour recall questionnaire was used. Nutrient values of home foods were collected during a weekend day, and nutrient values containing a combination of both home and school foods were collected during a weekday. Fisher’s exact test or 2 test and t test were used for analyses. Mean nutrient contents of foods provided to the border Mexican-American children exceeded recommendations for total energy (P⬍0.001), total fat (P⬍0.001), saturated fat (P⬍0.001), carbohydrates (P⬍0.001), protein (P⬍0.001), sodium (P⬍0.001), and niacin (P⬍0.001). Foods offered were also significantly insufficient in fiber (P⬍0.001), vitamin A (P⬍0.001), and potassium (P⬍0.001). Nutrition interventions targeting low-income border Mexican-American families should emphasize the need and importance of
N. Mier is assistant professor in Social and Behavioral Health at the South Texas Center School of Rural Public Health, Health Science Center, Texas A&M University System, McAllen. V. Piziak is chief of Endocrinology and professor of Medicine at the Health Science Center, Texas A&M University System, Temple. D. Kjar is a biostatistician at Scott & White, Temple, TX. O. Castillo-Ruiz is professor in Nutrition, G. Velazquez is chief of Food and Technology, M.E. Alfaro is a college graduate in Nutrition, and J. A. Ramirez is director of Graduate Studies, Tamaulipas Autonomous University Reynosa-Aztlan Campus, Reynosa, Mexico. Address correspondence to: Nelda Mier, PhD, South Texas Center School of Rural Public Health, Health Science Center, Texas A&M University System, 2101 South McColl Rd, Room 134, McAllen, TX 78503. E-mail: [email protected] Copyright © 2007 by the American Dietetic Association. 0002-8223/07/10702-0006$32.00/0 doi: 10.1016/j.jada.2006.11.013
© 2007 by the American Dietetic Association
providing children with diets that meet the Recommended Dietary Allowances. J Am Diet Assoc. 2007;107:311-315.
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reschool children from underserved minority groups are at high risk of both obesity and malnutrition because of eating habits that do not meet the Dietary Guidelines for Americans (1,2). In particular, MexicanAmerican preschool children are at higher risk of becoming obese than white non-Hispanic children (2-4). Data from National Health and Nutrition Examination Surveys between 1999 and 2004 indicate that the prevalence of overweight (body mass index for age ⱖ95 percentile) among Mexican-American children 2 to 5 years of age increased from 10.9% to 19.2% (3). Several other studies found that young Mexican-American children are twice as likely to be overweight or at risk of overweight than non-Hispanic white, black, and Asian children (3,5-7). Prevalence data collected in the Texas–Mexico border region show that 18.1% of 2,376 Mexican-American preschool children were obese (body mass index for age ⱖ97 percentile) (8,9). Part of the increase in childhood obesity can be explained by parental child-feeding practices. Studies show that when parents consume a high-energy-dense diet, children are more likely to have a similar diet (10,11). Children’s food preferences have also been associated with parental influence (10-16). Notwithstanding the considerable research assessing what is offered to and consumed by school-aged children in elementary to high school grades (17-20), there is scarce research examining the adequacy of nutrient contents of foods offered in a combined home and school setting to Mexican-American preschoolers living in the United States–Mexico border region. Nutrition research focusing on the border region is of great importance. Forty-nine percent of the border population is primarily of Mexican ancestry (21). This population is medically underserved and poor (21-24), and about 75% of adults are either overweight or obese (25). Moreover, almost 16% of border residents suffer from type 2 diabetes, a rate higher than the national rate in Mexico (14.9%) and the United States (13.9%) (25). The purpose of this study was to determine if nutrients offered to border Mexican-American preschool children met the Recommended Dietary Allowances. Nutrient contents of two dietary patterns were compared with recommendations (26,27), one composed exclusively of home foods and one containing a combination of home and
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school foods. We hypothesized that Mexican-American preschool children living at the border have diets offered at home and at a combined home and school setting that exceed recommendations for total energy and most macronutrients. METHODS Participants and Setting Participants were Mexican-American children 3 to 5 years of age attending two full-day Head Start centers in the easternmost area of the Texas–Mexico border region. In this region, a majority of the population is of Mexican descent (87%), and Spanish is spoken in three quarters of homes. Also, this population is young (38% under age 19) compared with state (31%) and national (29%) populations. In addition, two thirds of individuals under 25 years of age have less than a ninth-grade education. Access to medical care is limited and the major metropolitan areas in the region rank last in the nation in per capita income (24,28). Although 232 children were eligible to participate, this study included data from 198 children for whom there were no missing data. Participants were recruited using a convenience sampling technique and a majority were male (55%). Data were collected in 2003. This study received approval from the Institutional Review Board of Scott & White* and the Texas A&M University System, and informed consent was obtained from parents. Study Design and Measurement Parents of the children were asked to report the foods they offered to their child during a weekend day and a weekday. Parental information was obtained using a selfadministered precoded 24-hour recall that reflected foods offered to young Mexican Americans in the Texas–Mexico border area. A precoded food list was developed for this study by the researchers, based on feedback from Head Start staff as well as the Head Start daily menu. The precoded 24-hour recall was administered to 13 parents to test for readability, appropriateness of food list, and general ease of survey administration. This type of instrument was used because it is brief, inexpensive, and easily administered. Although the instrument used in the current study has not been validated, previous studies indicate that self-administered precoded 24-hour food recalls are a valid method to assess diets of young children (29-33). In addition, single-day dietary data are adequate for comparisons of groups if the sample sizes are sufficiently large (34,35). Nine teachers were trained to provide parents a detailed explanation of the study purpose and methods. Questionnaires were handed out in class and children were asked to take them home to their parents for completion. The questionnaire elicited information from parents about yesterday’s foods offered to their child for 1
*Scott & White is an institution that combines a clinic, hospital, and health plan and serves Central Texans. Scott & White’s main facilities are located in Temple, TX.
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weekday and 1 weekend day. The questionnaire was in English or Spanish and met literacy levels of participants. Weekday data also included foods offered to the children through the daily Head Start menu. For analysis purposes, we created two categories: the “home diet” and the “school plus home diet.” The home diet included data obtained from the parents describing foods offered to the children exclusively at home during a weekend day. The school-plus-home diet computed nutrient values obtained from both parental reports and foods listed on the daily menu served by Head Start on the weekday reported by the parents. The school menu offered two meals and snacks to children and met two thirds of recommendations (36). In addition, this study was based on values from the Dietary Reference Intakes for the 4- to 8-year-old age group (26) and the National Cholesterol Education Program guidelines (27) to compare diets and recommendations. Statistical Analyses Nutrient contents of dietary patterns were averaged and compared to recommendations. Nutrient values were computed using NutriPac (NutriPac, v1.5, 1992-2003, Mexico City, Mexico), which is software that includes food-composition data appropriate for food intake of our population. Mean energy, macronutrients, and selected micronutrient contents of foods were analyzed (total energy, total fat, saturated fat, cholesterol, protein, carbohydrate, saturated fat, fiber, calcium, iron, magnesium, zinc, potassium, sodium, vitamin A, C, thiamin, riboflavin, B-6, B-12, niacin, and folate). Differences in nutrient contents between diets were analyzed using 2 test or Fisher’s exact test. A t test was used to compare nutrient contents of dietary patterns with recommendations. The SAS software program (SAS Institute Inc, v8.2, 1999, Cary, NC) was used to conduct statistical analyses. A P value ⬍0.05 was considered significant for all statistical tests conducted. RESULTS AND DISCUSSION The Table details mean contents of micronutrients, vitamins, and minerals of each dietary pattern in comparison with the Recommended Dietary Allowances. Dietary patterns exceeded recommendations for some of the macronutrients. The mean value of total energy in both dietary patterns significantly exceeded (1.5 times) recommendations (P⬍0.01). Total fat and saturated fat were almost double the recommendations (P⬍0.01). Considering that the acceptable upper limit amount for carbohydrates is 227 g (65% of the caloric intake) based on recommendations for children in this age group (not shown in the table), the mean value of carbohydrate content significantly exceeded the upper limit recommendations by almost 60% (P⬍0.001) in both dietary patterns. The mean value of protein exceeded by almost five times (P⬍0.001) the recommended amount in both diets. In addition, the mean value of fiber was significantly below the recommended level by almost 50% (P⬍0.001). Mean values of both dietary patterns met recommendations for most vitamins, except vitamin A. Only one quarter of the children were offered the recommended
Table. Mean amounts of nutrients categorized by dietary pattern offered to Mexican-American preschool children on the Texas–Mexico border and compared to recommendations Nutrient
Home diet (nⴝ106)
School-plus-home diet (nⴝ92)
Energy (kcal) Total fat (g) Saturated fat (g) Kcal from fat Kcal from carbohydrates Carbohydrates (g)e Protein (g)e Fiber (g)e Cholesterol (mg) Vitamin A (g RAEg)e Vitamin C (mg) Thiamin (mg)e Riboflavin (mg)e Niacin (mg) Vitamin B-6 (mg) Folate (g DFEh) Vitamin B-12 (g)e Calcium (mg)e Iron (mg) Magnesium (mg) Zinc (mg) Potassium (mg) Sodium (mg)
4™™™™™™™™™™™™™™™™™ mean⫾SD b ™™™™™™™™™™™™™™™ 3 2,353⫾1,045cx 2,623⫾901dx 67.9⫾38.4cx 81.2⫾31.4dx 24.1⫾14.0cx 33.1⫾13.3dx cx 611.1⫾345.6 730.8⫾282.6dx 1,452⫾692cx 1,520⫾628dz cx 363⫾173 380⫾157dx 79.3⫾40.9cx 102.3⫾33.7cx 9.0⫾5.2cx 12.1⫾4.7cx 342⫾241c 312⫾197c cx 292⫾206 325⫾232cy 44⫾52cx 41⫾50cy cx 1.4⫾0.8 1.7⫾0.8dx 1.8⫾1.0cx 2.6⫾1.2dx cx 16.5⫾10.2 18.1⫾7.6dx 1.1⫾0.6cx 1.4⫾0.6dx cz 355⫾264dx 263⫾296 6.2⫾7.7cx 8.0⫾7.4dx cy 1,015⫾602 1,692⫾589dx 17.1⫾12.0cx 29.0⫾11.6dx cx 218⫾136 365⫾136dx 7.6⫾4.4cx 10.6⫾3.5dx 2,454⫾159cx 3,451⫾1,558c 2,488⫾1,444cx 2,301⫾1,125cy
Recommendationsa 1,400 46 15.5 414 520 130 19 25 ⬍300f 400 25 0.6 0.6 8 0.6 200 1.2 800 10 130 5 3,800 1,200
a
Represents Recommended Dietary Allowances determined by the Institute of Medicine for the 4- to 8-year-old age group. SD⫽standard deviation. Mean values by type of diet with the same superscript do not differ significantly (P⬎0.05). e Fisher exact test was used instead of 2 test to establish significant differences between diets. f This value is the acceptable level determined by the National Cholesterol Education Program for children over 2 years of age. g RAE⫽retinol activity equivalents. h DFE⫽dietary folate equivalent. x Statistically significant difference between mean and recommendations at P⬍0.001. y Statistically significant difference between mean and recommendations at P⬍0.01. z Statistically significant difference between mean and recommendations at P⬍0.05. b
cd
level of vitamin A in both dietary patterns (not shown in the Table). The Table shows that the home diet met approximately two-thirds of the recommended level of vitamin A (P⬍0.001). The school plus home diet met 80% of the recommended value of vitamin A (P⬍0.01). Although the mean contents of both dietary patterns exceeded recommendations for vitamin C as shown in the Table, half of the participants (n⫽50 in the home diet and n⫽48 in the school plus home diet) were not offered the recommended levels of vitamin C (not shown in the Table). Both home diet and the school-plus-home diet met recommendations for calcium, iron, magnesium, and zinc, but failed recommendations for potassium and exceeded recommendations for sodium. Children’s foods contained more than 1.5 times the recommendations for sodium in both the home diet (P⬍0.001) and the school-plus-home diet (P⬍0.01). In summary, Mexican-American border preschool children in this study were provided with nutrient contents from home foods during a weekend day and from a com-
bination of both home and school foods during a weekday that exceeded considerably the recommendations for several nutrients, including total energy, total fat, saturated fat, carbohydrates, protein, sodium, and niacin. Food contents were significantly insufficient in fiber, vitamin A, and potassium. Consistent with a study by Acosta and colleagues (37), this research found that mean energy of foods offered to Mexican-American children exceeded recommendations. In addition, the present findings indicating mean protein contents exceeding recommendations were consistent with previous studies (37-39). However, while previous studies found that calcium intake among preschool Mexican-American children did not meet recommendations, the present study found an adequate level of calcium offered to a majority of participants. Discrepancy across studies might be related to differences in dietary measurements used. All studies mentioned used modified 24-hour recalls by parental report, and only one (39) also included an observational method. Another possible explanation might be regional and socioenvironmental fac-
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tors influencing feeding practices of Mexican-American children living on the border. Thus, discrepancy across studies warrants additional examination. Although our study found that mean fat contents of foods provided to our cohort exceeded recommendations, the percentage of energy intake from fat (25% in the home diet and 27% in the school-plus-home diet) did not exceed recommendations (30%) (40). Also, results indicate that the children’s diet exceeded recommendations for carbohydrates and protein, but was significantly insufficient in fiber. These findings indicate that border Mexican-American children were offered diets rich in processed and sugary foods and composed of large portions. This study also indicates that a majority of the children were offered dietary patterns deficient in vitamin A. A low consumption of vitamin A among border MexicanAmerican children should be addressed as a potential health risk related to respiratory infection, impaired wound healing, and vision complications (41,42). Although the findings in our study showing that vitamin A was below recommendations are supported by Looker and colleagues (43,44) and Larson and colleagues (38), our results differ from other researchers (37,45), who found an adequate intake of this vitamin. Results from our study showing a deficiency in both vitamin A and C reflect a diet insufficient in fruits and vegetables. This study has several limitations. Because of the convenience sampling technique used, findings of this study can only be generalized to Mexican-American children living at the Texas–Mexico border from poor families that speak Spanish at home, have low education levels, and have insufficient access to health care. Additional research is needed to verify these findings in a larger randomized sample of Mexican-American children along the border. Another limitation was the self-report instrument used. Although this tool was used to estimate nutrients of foods, it did not measure actual intake by direct observation. Also, validity and reliability were not assessed. Finally, it is difficult to code mixed dishes with this instrument (30). Limitations related to the instrument could have led to some inaccuracies in nutrient estimation. CONCLUSIONS Consumption of diets high in energy (compared with needs for growth and physical activity) can put border Mexican-American preschool children at risk of obesity. Nutrition interventions targeting low-income border Mexican-American families should emphasize the need and importance of providing children with diets that meet recommendations. References 1. Bronner YL. Nutritional status outcomes for children: Ethnic, cultural, and environmental contexts. J Am Diet Assoc. 1996;96:891-903. 2. Strauss RS, Pollack HA. Epidemic increase in childhood overweight, 1986-1998. J Am Med Assoc. 2001; 286:2845-2848. 3. Ogden CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM. Prevalence of overweight and obesity in the United States. JAMA. 2006;295: 1549-1555.
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4. Mei Z, Scanlon KS, Grummer-Strawn LM, Freedman DS, Yip R, Trowbridge FL. Increasing prevalence of overweight among US low-income preschool children: The Centers for Disease Control and Prevention pediatric nutrition surveillance, 1983 to 1995. Pediatrics. 1998;101:E12. 5. Stolley MR, Fitzgibbon ML, Dyer A, Van Horn L, KauferChristoffel K, Schiffer L. Hip-Hop to Health Jr., an obesity prevention program for minority preschool children: Baseline characteristics of participants. Prev Med. 2003;36:320-329. 6. Park MK, Menard SW, Schoolfield J. Prevalence of overweight in a triethnic pediatric population of San Antonio, Texas. Int J Obes. 2001;25:409-416. 7. Nelson JA, Chiasson MA, Ford V. Childhood overweight in a New York City WIC population. Am J Public Health. 2004;94:458-462. 8. Mier N, Piziak V. Development of a nutrition demonstration program for Hispanic preschool children living along the United States-Mexico border. Paper presented at the Border Health Association 62nd Annual Meeting. Abstract No. 12. June 10, 2004, Juarez, Mexico. 9. Piziak V. Worldwide childhood obesity. Paper presented at Binational Health Week Forum. Epidemic of Childhood Obesity; October 10, 2004, McAllen, TX. 10. Oliveria SA, Ellision RC, Moore LL, Gillman MW, Garrahie EJ, Singer MR. Parent-child relationships in nutrient intake: The Framingham Children’s Study. Am J Clin Nutr. 1992;56:593-598. 11. Anderson PM, Butcher KF. Childhood obesity: Trends and potential causes. Future Child. 2006;16:19-45. 12. Melgar-Quiñonez HR, Kaiser LL. Relationship of child-feeding practices to overweight in low-income Mexican-American preschool-aged children. J Am Diet Assoc. 2004;104:1110-1119. 13. Faith MS, Keller KL, Johnson SL, Pietrobelli A, Matz PE, Must S, Jorge MA, Cooperberg J, Heymsfield SB, Allison DB. Familial aggregation of energy intake in children. Am J Clin Nutr. 2004;79:844-850. 14. Klesges RC, Stein RJ, Eck LH, Isbell TR, Klesges LM. Parental influence on food selection in young children and its relationships to childhood obesity. Am J Clin Nutr. 1991;53:859-864. 15. Birch LL, Davison KK. Family environmental factors influencing the developing behavioral controls of food intake and childhood overweight. Pediatr Clin North Am. 2001;48:893-907. 16. Hodges EA. A primer on early childhood obesity and parental influence. Pediatr Nurs. 2003;29:13-16. 17. Jimenez-Cruz A, Bacardi-Gascon M, Jones EG. Consumption of fruits, vegetables, soft drinks, and highfat-containing snacks among Mexican children on the Mexico-U.S. border. Arch Med Res. 2002;33:74-80. 18. Jiménez-Cruz A, Bacardí-Gascón M, Spindler AA. Obesity and hunger among Mexican-Indian migrant children on the US-Mexico border. Int J Obes Relat Metab Disord. 2003;27:740-747. 19. Novotny R, Boushey C, Bock MA, Peck L, Auld G, Bruhn CM, Gustafson D, Gabel K, Jenson JK, Misner S, Read M. Calcium intake of Asian, Hispanic and white youth. J Am Coll Nutr. 2003;22:64-70. 20. McKenzie J, Dixon LB, Smiciklas-Wright H, Mitchell
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