Location: Children's Nutrition Research Center2013 Annual Report
1a. Objectives (from AD-416):
Childhood obesity is a major public health problem in the U.S. and successful approaches to prevent obesity are needed. The prevalence of overweight in preschool children has more than doubled in the past two decades. Currently, a third of children in the United States are at risk of overweight, while 17% are overweight. A greater concern is that most existing obesity prevention intervention approaches thus far have been found to be largely ineffective. Diverse novel behavioral, genetic, and biological methods and models are needed to better understand the causes and find effective ways to combat this problem. Children's Nutrition Research Center scientists will address these issues through targeting the following research objectives: 1) determine the extent to which relationships between appetite-related genetic factors and dietary intake are mediated by subjective feelings of hunger, satiety, and other psychosocial variables in children; 2) determine the extent to which relationships between activity-related genetic factors and physical activity are mediated by subjective feelings of enjoyment and related psychosocial variables in children; 3) investigate the effectiveness of community-based intervention strategies to prevent childhood obesity and its associated health risks in 8- to 12-y-old Hispanic children with BMI >/= 85th percentile; 4) develop and evaluate family-centered intervention strategies for the pediatric primary care setting to prevent childhood obesity; 5) develop and evaluate the effectiveness of a culturally appropriate, web-based, dietary and physical activity intervention for preventing obesity in high school students; 6) develop and evaluate the effectiveness of novel, multi-media, diet and/or physical activity interventions for preventing obesity in youth; 7) develop and evaluate a model of childhood obesogenic environments based on parent-child dynamics affecting child eating behaviors and body weight status; 8) determine environmental factors and eating pattern typologies associated with obesity and related diseases in children, adolescents, and young adults using extant datasets; 9) identify promising theoretical approaches, mediators, and intervention components of nutrition and physical activity behavior change in children using extant datasets; 10) identify risk factors, moderators, and mediators for obesity and obesity-related behaviors, including dietary, physical activity and lifestyle factors using extant datasets; 11) evaluate relationships between parent and child beliefs about physical activity, and their relationship with child physical activity, sedentary behavior, and weight status using extant datasets; 12) determine obesity-related metabolic and body composition responses to exercise programs with and without a dietary intervention in lean and obese adolescents; and 13) develop and test pilot interventions to increase and sustain physical activity at a level consistent with the Dietary Guidelines for Americans (DG) in urban African- and Mexican-American children and families.
1b. Approach (from AD-416):
A multidimensional approach will be undertaken to address the obesity research conducted at the Children's Nutrition Research Center. In summary, investigators will address childhood obesity through research in genetics, biology, behavioral modeling, and by the implementation of a wide range of interventions. Researchers will investigate the effects of a controlled exercise program alone as compared to exercise with a diet intervention and determine the impact on numerous biological measures of the research participants. Genes related to satiety or physical activity signaling pathways will be examined by researchers as they learn the association of eating and physical activity experiences in children. Additional research will permit new models of how known genes may be influencing diet and physical activity practices. Researchers will develop, test, and validate innovative youth behavioral models and validate a measure of youth physical activity problem solving ability. Additional models will be developed to understand the functional relationships of behavioral factors that influence the weight status of children, as a result of examining parent and child characteristics (individually and combined) to ascertain their contributions to the probability of pediatric obesity. Model refinement will occur by employing dyadic and mixture modeling approaches to account for latent heterogeneity in how these factors are functionally inter-related within the given population. Assessment of the validity of current theories of obesity-related behavior change will be conducted through mediating variable analyses of existing datasets. Several interventions will be conducted in order to establish functional programs that will reduce obesity and/or further weight gain. A family-based randomized controlled trial will be conducted to test the effectiveness of diet behavior modification, structured aerobic exercise, or diet behavior modification plus structured aerobic exercise for obesity prevention and improvement in fitness, health risks, and psychological state in at-risk children. Research studies will also evaluate the effectiveness of a culturally appropriate, web-based, dietary and physical activity intervention for preventing obesity in high school students when compared with a control group. Weight, dietary and physical activity behaviors, and psychosocial mediating variables will be measured and compared to determine the effectiveness of specific web-based interventions. Furthermore, as a result of these interventions, models will be developed and formative work performed to evaluate the developed model for obesity prevention.
3. Progress Report:
Significant research progress was accomplished during the year. To review the progress, please refer to project 6250-51000-053-10S (Project 1), 6250-51000-053-20S (Project 2), 6250-51000-053-30S (Project 3), 6250-51000-053-40S (Project 4),6250-51000-053-50S (Project 5), 6250-51000-053-60S (Project 6), and 6250-51000-053-70S (Project 7).
1. Categorizing ways that parents get kids to eat vegetables. There has been no theory-based measure that assesses both likely to be effective and likely to be ineffective vegetable parenting practices for use in research with young children (3-5 years old). Researchers at the Children's Nutrition Research Center in Houston, Texas, developed a measure that included 31 items across theory-predicted responsiveness (or warmth), control and structure (or supportiveness of the environment) aspects of both effective and ineffective vegetable parenting practices. The predicted categories were confirmed by analysis of questionnaire data, and the pattern of findings suggests that parents use both effective and ineffective practices. The questionnaire is now available as a resource for use by researchers to study the development of young children's eating habits.
2. Minority children meet Dietary Guidelines for physical activity. The current dietary guidelines recommend that children engage in 60 minutes of physical activity daily. However, children are engaging in considerably less physical activity now than they were 20 years ago, and this decrease coincides with increased prevalence of obesity in youth. Scientists at the Children's Nutrition Research Center in Houston, Texas, have developed a program to increase physical activity in children in order to meet dietary guideline recommendations for physical activity. We were able to demonstrate that the participants of the treatment group not only improved their physical activity levels but also maintained these levels over time. This is particularly important for minority children who are at greater risk for obesity-related health problems. These results have important implications for future policy development.
3. How do feeding practices of low-income mothers compare to current recommendations? Little is known about whether mothers follow current pediatric recommendations for feeding of young children, especially among low-income families who are at a higher risk for obesity. The American Academy of Pediatrics in the Pediatric Nutrition Handbook (5th edition) states that "Adults should decide when food is offered or available and the child should be left to decide how much and whether to eat at a given eating occasion." Researchers at the Children's Nutrition Research Center, Houston, Texas, used direct observation of dinner meal interactions in low-income Latina and Black families to gather descriptive data on feeding practices. Results showed that maternal feeding practices were not consistent with current recommendations in that 1) many mothers spent considerable time encouraging eating—often in spite of the child's insistence that he or she was finished, 2) mothers talked little about food characteristics, 3) they rarely referred to children's feelings of hunger and fullness, and 4) they spent more time focusing on table manners rather than teaching eating skills. Most of the mothers in this study did not engage in feeding practices that are consistent with current pediatric feeding recommendations. These results are important because they can be used to inform the development of feeding interventions in low-income families that are at the greatest risk for developing childhood obesity.
4. Adapting an adult dietary self-report tool to children. It is not clear whether the National Cancer Institute's Automated Self-Administered 24-Hour Dietary Recall (ASA24) that was simplified to meet the needs of children still provides accurate estimates of nutrient intake. Researchers at the Children's Nutrition Research Center in Houston, Texas, adapted the ASA24 to be child-friendly by removing: (1) foods not likely to be consumed by children based on previous analyses of national dietary data and (2) food detail questions (probes) to which children are unlikely to know the answers. No differences were found between the ASA24 and the simulated child-friendly recall, except for total sugar and vitamin C. This research demonstrated that it is feasible to reduce child response burden without significantly affecting the nutrient results.
5. Studying the impact of breakfast on cardiometabolic risk factors. The Centers for Disease Control and Prevention identifies that more than one-third of US adults are obese. Researchers at the Children's Nutrition Research Center in Houston, Texas, conducted secondary data analyses that examined the relationship of skipping breakfast and type of breakfast consumed with cardiometabolic risk factors in young adults. Data from the 1999–2000 NHANES showed that 37.2% and 25.9% of US young adults aged 19–29 years and 30–39 years, respectively, skipped breakfast. In this sample of US young adults, eating a breakfast that included a ready-to-eat-cereal was associated with a lower prevalence of overweight/obesity, abdominal obesity, and several other cardiometabolic risk factors in contrast to the potential adverse metabolic effects that were found from skipping breakfast. Health professionals should encourage regular consumption of a nutritious breakfast (e.g., one that includes a ready-to-eat-cereal) in the young adult population, and interventions to increase the prevalence of breakfast consumption in the young adult population are warranted.
6. Scales for a Model of Goal-Directed Vegetable Parenting Practices (MGDVPP). Vegetable intake has been related to lower risk of chronic illnesses in the adult years. The habit of vegetable intake should be established early in life, but many parents of preschoolers report not being able to get their child to eat vegetables. The Model of Goal-Directed Behavior (MGDB) adds emotional and motivational variables to existing highly predictive models to understand why people do (or do not do) targeted behaviors. The Model of Goal-Directed Vegetable Parenting Practices provides possible determinants and may help explain why parents use effective or ineffective vegetable parenting practices. Researchers at the Children's Nutrition Research Center in Houston, Texas, developed new scales to measure constructs in MGDVPP which include 164 items extracted from questionnaire data. These scales are now available for use by researchers who are interested in understanding or encouraging parents' use of effective and ineffective vegetable parenting practices.
7. Diet quality inversely associated with cardiovascular risk factors. Use of diet quality indexes has become widespread, since these indexes allow for evaluation of the total diet in relationship to select nutrient intake, compliance with dietary recommendations, and chronic disease risk. Researchers at the Children's Nutrition Research Center in Houston, Texas, conducted a study and confirmed that overall diet quality was inversely related to cardiovascular risk factors in adults, emphasizing the importance of compliance with dietary recommendations and chronic disease risk. Results showed that diet quality as assessed by a specific diet-quality index called the Healthy Eating Index, varied according to sociodemographic factors such as age, gender, and race-ethnicity, as well as lifestyle factors such as exercise, smoking, and alcohol use. The percentage of adults who reported smoking, drinking alcohol, and participating in sedentary-to-light physical activity decreased with increased diet quality. Our overall results suggest that Healthy Eating Index-2005 is inversely associated with several cardiovascular risk factors in the US population. However, the overall effectiveness of these guidelines in disease prevention needs to be investigated further in prospective studies and among different sub-populations.
8. The effects of maternal eating patterns on maternal feeding and child eating. Recent research has demonstrated the importance of maternal feeding practices and children's eating behavior in the development of childhood obesity. Children's Nutrition Research Center scientists in Houston, Texas, conducted a study to examine the relations between maternal and child eating patterns, and to examine the degree to which these relationships were mediated through maternal feeding practices. We found that picky eating and the desire to eat in children were related to emotional eating in mothers. By better understanding the complex relationships between maternal eating patterns, feeding practices, and child eating patterns, we can better know how to educate and create positive feeding/eating environments that may potentially reduce rates of overweight and obesity among children.
9. Categorizing ways that parents influence their child's TV watching. Behavioral researchers focusing on obesity prevention in children question whether the same scale of how parents influence their children's TV use is appropriate for parents of children of different ages. Researchers at the Children’s Nutrition Research Center in Houston, Texas, combined data from three existing studies that included 358 children between the ages of 3 and 12 years of age. Their analyses revealed that items worked differently across the children's age groups, more than across parental education or language groups. We now know that researchers will need to modify the scales to minimize differences in measurement across children of different ages.
10. Correlations between mother-child dyad intakes of foods. Family dietary practices have been shown to be an important determinant of the quality of children's diets, with parents serving as gatekeepers that can serve as role models for their children's health-related behaviors, including diet. The objective of this study conducted by researchers at the Children's Nutrition Research Center in Houston, Texas, was to expand the current literature to include an examination of the resemblance in intakes of foods, within the context of a meal, among mother-child groups from families of limited incomes. Mothers and children who were served larger amounts of total food/beverages consumed more. Our findings support other studies on the resemblance in dietary intakes among mother-child groups and that larger portion sizes of foods served was related to higher amounts of those foods consumed. It is important that food and nutrition professionals provide guidance that encourages their intake of major food groups, so the mothers can model healthier food consumption behaviors for their children.
11. Conference report on energy balance related parenting practices. Although parents are believed to provide strong influence on children's behavior, severe problems have been identified in measures of obesity-related (i.e., diet, physical activity, and screen media) parenting practices. These problems have inhibited the quality of the research in this area, and to change this situation, researchers at the Children's Nutrition Research Center in Houston, Texas, held a conference and from this were able to develop a special report. The conference presentations reviewed the relevant literature and working group discussions and identified research needed to bring clarity and precision to measures of these constructs. The publications from the presentations and working group discussions will appear as a special issue of Childhood Obesity. Several groups who attended the conference are now developing new measures of obesity-related parenting practices, which offers a promise of improving research in this area.
12. Food consumption at dinner by preschool children. A dinner meal is consumed by approximately 95% of preschool children, yet few studies have characterized the dinner meal within a broader environmental context. Data from this study, conducted by the Children's Nutrition Research Center researchers in Houston, Texas, showed that plate waste and variation in amounts served and consumed was substantial. A very large percentage of the mothers did not consume dinner with their child. The results confirm that serving larger amounts of food resulted in increased intake at the dinner meal among preschool children. A lack of consistent guidelines on the amounts preschool children should consume at dinner prevents one from drawing firm conclusions about the appropriateness of amounts and types of foods served during this specific meal. Hopefully, future studies will generate data that will provide the foundation regarding the amount of food to be offered by parents at dinner meals based on current consumption patterns.
Cullen, K.W., Thompson, D.J., Boushey, C., Konzelmann, K., Chen, T.A. 2013. Evaluation of a web-based program promoting healthy eating and physical activity for adolescents: Teen Choice: Food and Fitness. Health Education Research. 28(4):704-714.