Lawrence D. Hammer

Pursuit of thinness and onset of eating disorder symptoms in a community sample of adolescent girls: A three-year prospective analysis.

Community-based prospective studies are needed to shed light on mechanisms that may influence development of eating disorders and identify variables that could serve as potential targets for prevention efforts. In this paper we examine level of weight preoccupation and other variables prospectively associated with age of onset of eating disorder symptoms over a 3-year interval in a community sample (N = 939) of young adolescent girls. 3.6% (32/887) experienced onset of symptoms over the interval. Only one factor, a measure of Weight Concerns, was significantly associated with onset (p < .001). Girls scoring in the highest quartile on the measure of Weight Concerns had the shortest survival time (12% incidence by age 14.5) and those scoring in the lowest quartile had the highest survival time (2% incidence by age 14.5; p < .001). This finding is consistent with both theoretical and clinical perspectives and represents one of the first prospective demonstrations of a linkage between weight and body shape concerns and later onset of eating disorder symptoms. An understanding of the independent variables that predispose girls to development of symptoms is a useful step towards the establishment of a rational basis for the choice of a prevention intervention target.

Behavioral Validation, Precursors, and Concomitants of Picky Eating in Childhood

OBJECTIVES To validate the concept of parent-reported picky eating using objective, laboratory-based measures and to identify both child and parental precursors and concomitants of picky eating. METHOD One hundred thirty-five infants were monitored from birth to 5.5 years. Behavioral measures of picky eating were obtained from standardized feedings at ages 3.5 and 5.5 years in the laboratory and at home. Child precursors were measures of infant sucking behavior; parental precursors were disinhibition of eating, restrained eating, body dissatisfaction, and body mass index. Parentally reported attitudes and behaviors thought to be related to pickiness and parental concomitants were taken from the Stanford Feeding Questionnaire. Child Temperament was assessed by the Childrens Behavior Questionnaire. RESULTS Picky eaters ate fewer foods and were especially more likely to avoid vegetables. Picky girls decreased their caloric intake between ages 3.5 and 5.5, whereas all other children increased their caloric intake. None of the included parental precursors was significantly related to pickiness. Picky eaters demonstrated a different sucking pattern with fewer sucks per feeding session at weeks 2 and 4. Finally, picky children displayed more parent-reported negative affect than nonpicky children. CONCLUSIONS Parentally reported picky eating is associated with a consistent pattern of inhibited and selective eating beginning in infancy.

Risk factors for the emergence of childhood eating disturbances: A five-year prospective study

OBJECTIVE Research suggests that eating problems are often present by preadolescence, yet little is known about the age of emergence of these early eating disturbances or risk factors for these behaviors. Thus, we investigated the timing of onset of disturbed eating during childhood and the predictors of these behaviors. METHOD These aims were addressed by following a sample of children and their parents (N = 216) for the first 5 years of the childrens lives. RESULTS Data suggested that the risk for emergence of inhibited eating, secretive eating, overeating, and vomiting increased annually through age 5. Maternal body dissatisfaction, internalization of the thin-ideal, dieting, bulimic symptoms, and maternal and paternal body mass prospectively predicted the emergence of childhood eating disturbances. Infant feeding behavior and body mass during the first month of life also predicted the emergence of these behaviors. DISCUSSION Results suggest that eating disturbances emerge during childhood and may be a function of certain parental and child characteristics.

Ethnicity and body dissatisfaction: Are Hispanic and Asian girls at increased risk for eating disorders?

PURPOSE To compare prevalences and correlates of body dissatisfaction among white, Hispanic, and Asian girls. METHODS A total of 939 6th and 7th grade girls (mean age 12.4 years) attending four middle schools in northern California completed self-administered assessments of age, ethnicity, desired body shape, parent education levels, mothers and fathers body shapes, pubertal stage, and body dissatisfaction. Body dissatisfaction was assessed with the Body Dissatisfaction scale of the Eating Disorder Inventory. Height, weight, triceps skinfold thickness, and waist and hip circumferences were measured by trained examiners. RESULTS Hispanic girls reported significantly greater body dissatisfaction than white girls, with Asian girls in-between. After adjustment for body mass index (weight/height), normal and overweight white, Hispanic, and Asian girls reported similar levels of body dissatisfaction. However, among the leanest 25% of girls, Hispanics and Asians reported significantly more body dissatisfaction than white girls. Body mass index was the strongest independent predictor of increased body dissatisfaction in all three ethnic groups. Shorter height among white girls and taller height among Asian girls also made significant independent contributions. Parent education level, a measure of socioeconomic status, was not significantly associated with body dissatisfaction. CONCLUSIONS Body dissatisfaction is not limited to white girls in middle and upper socioeconomic strata. These findings suggest Hispanic and Asian girls may be at greater risk for adopting eating disorder behaviors than previously recognized.

Influence of early feeding style on adiposity at 6 years of age

In a previous study we found that a vigorous infant feeding style measured in the laboratory at 2 and 4 weeks of age predicted the degree of adiposity at 1 and 2 years of age. A follow-up of this cohort of infants at 3 and 6 years of age is now reported. Factors predicting adiposity, measured by body mass index at 3 years of age, were pressure of suckling, with high-pressure sucking (denoting a vigorous feeding style) associated with greater adiposity, and time of introduction of solid food, with delayed introduction of solid food or breast-feeding longer than 5 months, or both, being associated with greater adiposity. Predictive factors at 6 years of age were adiposity at birth, with greater adiposity at birth predicting greater fatness at 6 years, parental education, with less education associated with fatness, and a prolonged period of breast-feeding with delayed introduction of solid food. These factors accounted for 40.4% of the variance in adiposity at 3 years of age and 31.2% at 6 years. The effects of social learning on body mass index, indicated by parental educational level, appear to strengthen over time, whereas the effects of the vigorous feeding style wane.

Can mothers influence their child's eating behavior?

This study examined the relationship between general maternal parenting style, maternal eating cues, and a childs eating behavior during mealtime. We expected that the general style would relate to the number of specific eating cues and that mothers who used more eating prompts would have children that ate more and at a faster rate. Seventy-seven children (39 girls, 38 boys), aged 3.5 years, visited the laboratory with their mothers for a videotaped lunch. Videotapes of each laboratory visit were coded for the childs eating rate and maternal parenting style, which was measured as the level of maternal control and support and the number and type of eating prompts given during a meal. Caloric intake was also calculated. The number and rate of verbal and physical encouragements and discouragements were significantly related to measures of general maternal parenting style and meal duration. The rates of food offers, food presentations, and total prompts were all significantly related to the childs rate of calorie intake. However, a mothers level of support or control was not related to the childs eating behavior. Although general maternal parenting style did not predict the childs eating behavior, these behaviors were related to the frequency of maternal eating prompts, which in turn were significantly related to the number of calories eaten and the time spent eating by the child. Children who ate the fastest had mothers who delivered eating prompts at a higher frequency. These findings may have implications for the development of obesity later in childhood, as a function of rapid eating or of poor self-regulation.

Does a vigorous feeding style influence early development of adiposity

A prospective study of a cohort of healthy infants observed from birth to 2 years of age was carried out to investigate factors influencing the development of early adiposity. Infant suckling was measured in the laboratory twice during the first month of life. Multiple regression analyses revealed that parental educational level and a measure of feeding behavior, the interval between bursts of suckling, accounted for 18% of the variance in triceps skinfold measures at 1 year of age. A lower level of education and shorter interburst interval were associated with increased adiposity. Two feeding variables, pressure of suckling and the number of reported feeds per day, accounted for 21% of the variance in skinfold thickness at 2 years of age. Fewer, but larger, feeds and a higher sucking pressure were associated with a greater degree of adiposity. It seems that a vigorous infant feeding style, consisting of sucking more rapidly, at higher pressure, with a longer suck and burst duration, and a shorter interval between bursts of sucking, is associated with higher caloric intake and greater adiposity. The early development of this feeding style suggests that it may be a genetically endowed behavior. Breast-feeding protected against early adiposity only to the age of 6 months in this cohort of infants.

Increasing immunization coverage.

In 1977, the American Academy of Pediatrics issued a statement calling for universal immunization of all children for whom vaccines are not contraindicated. In 1995, the policy statement “Implementation of the Immunization Policy” was published by the American Academy of Pediatrics, followed in 2003 with publication of the first version of this statement, “Increasing Immunization Coverage.” Since 2003, there have continued to be improvements in immunization coverage, with progress toward meeting the goals set forth in Healthy People 2010. Data from the 2007 National Immunization Survey showed that 90% of children 19 to 35 months of age have received recommended doses of each of the following vaccines: inactivated poliovirus (IPV), measles-mumps-rubella (MMR), varicella-zoster virus (VZB), hepatitis B virus (HBV), and Haemophilus influenzae type b (Hib). For diphtheria and tetanus and acellular pertussis (DTaP) vaccine, 84.5% have received the recommended 4 doses by 35 months of age. Nevertheless, the Healthy People 2010 goal of at least 80% coverage for the full series (at least 4 doses of DTaP, 3 doses of IPV, 1 dose of MMR, 3 doses of Hib, 3 doses of HBV, and 1 dose of varicella-zoster virus vaccine) has not yet been met, and immunization coverage of adolescents continues to lag behind the goals set forth in Healthy People 2010. Despite these encouraging data, a vast number of new challenges that threaten continued success toward the goal of universal immunization coverage have emerged. These challenges include an increase in new vaccines and new vaccine combinations as well as a significant number of vaccines currently under development; a dramatic increase in the acquisition cost of vaccines, coupled with a lack of adequate payment to practitioners to buy and administer vaccines; unanticipated manufacturing and delivery problems that have caused significant shortages of various vaccine products; and the rise of a public antivaccination movement that uses the Internet as well as standard media outlets to advance a position, wholly unsupported by any scientific evidence, linking vaccines with various childhood conditions, particularly autism. Much remains to be accomplished by physician organizations; vaccine manufacturers; third-party payers; the media; and local, state, and federal governments to ensure dependable vaccine supply and payments that are sufficient to continue to provide immunizations in public and private settings and to promote effective strategies to combat unjustified misstatements by the antivaccination movement. Pediatricians should work individually and collectively at the local, state, and national levels to ensure that all children without a valid contraindication receive all childhood immunizations on time. Pediatricians and pediatric organizations, in conjunction with government agencies such as the Centers for Disease Control and Prevention, must communicate effectively with parents to maximize their understanding of the overall safety and efficacy of vaccines. Most parents and children have not experienced many of the vaccine-preventable diseases, and the general public is not well informed about the risks and sequelae of these conditions. A number of recommendations are included for pediatricians, individually and collectively, to support further progress toward the goal of universal immunization coverage of all children for whom vaccines are not contraindicated.

Early body mass index and other anthropometric relationships between parents and children

OBJECTIVE: To assess longitudinally the relationship between measures of adiposity in children over the first 8 y of life with that of their parents and to explore the role of parental adiposity in the development of childhood adiposity.DESIGN: Longitudinal study of measures of adiposity in children.SUBJECTS: A community sample from three health service systems including 114 children followed annually from infancy to age 8 and their 228 biological parents.METHODS: Measurements were assessed at baseline for parents (6 months post-partum for mothers) and at regular intervals for children beginning at age 2 months. Measurements included weight, height, triceps skinfold, subscapular skinfold, midarm circumference, waist and hip.RESULTS: The major findings were: (1) significant correlations between parental body mass index (BMI), both maternal and paternal, and their biological offspring first emerged at age 7; (2) children with two overweight parents had consistently elevated BMI compared to children with either no overweight parents or one overweight parent. These differences became significant beginning at age 7.CONCLUSIONS: This study supports the hypothesis that familial factors (biological and/or environmental) affecting the development of adiposity emerge at specific ages and are related to the adiposity of both parents.

The relationship between parental factors at infancy and parent-reported control over children's eating at age 7.

The objective of this study was to determine predictors of parental control over childrens eating. Data were obtained from 135 children and their parents from the Stanford Infant Growth Study. Assessments were obtained from parents at their childs birth and age 7. Parental body dissatisfaction at their childs birth predicted pressure to eat for both sons and daughters. In addition, minority status, parent being born outside of the United States, and a mothers early return to work predicted parental pressure to eat for sons. For daughters, an early maternal pushy feeding style also predicted parental pressure to eat. Parental hunger, a parental history of eating disorders and parent being born outside of the United States predicted food restriction for daughters. There were no predictors of food restriction for sons. We concluded that parental control appears not always to be simply a reaction to a childs lack of self-control or overweight, but may be present before such issues arise, particularly with the presence of certain cultural factors.