John Worobey

Early Influences on the Development of Food Preferences

The ability to perceive flavors begins in utero with the development and early functioning of the gustatory and olfactory systems. Because both amniotic fluid and breast milk contain molecules derived from the mothers diet, learning about flavors in foods begins in the womb and during early infancy. This early experience serves as the foundation for the continuing development of food preferences across the lifespan, and is shaped by the interplay of biological, social, and environmental factors. Shortly after birth, young infants show characteristic taste preferences: sweet and umami elicit positive responses; bitter and sour elicit negative responses. These taste preferences may reflect a biological drive towards foods that are calorie- and protein-dense and an aversion to foods that are poisonous or toxic. Early likes and dislikes are influenced by these innate preferences, but are also modifiable. Repeated exposure to novel or disliked foods that occurs in a positive, supportive environment may promote the acceptance of and eventually a preference for those foods. Alternatively, children who are pressured to eat certain foods may show decreased preference for those foods later on. With increasing age, the influence of a number of factors, such as peers and food availability, continue to mold food preferences and eating behaviors.

Come and Get It! A Discussion of Family Mealtime Literature and Factors Affecting Obesity Risk

The L.E.A.D. (Locate, Evaluate, and Assemble Evidence to Inform Decisions) framework of the Institute of Medicine guided the assembly of transdisciplinary evidence for this comprehensive, updated review of family meal research, conducted with the goal of informing continued work in this area. More frequent family meals are associated with greater consumption of healthy foods in children, adolescents, and adults. Adolescents and children who consume fewer family meals consume more unhealthy food. School-aged children and adolescents who consume more family meals have greater intakes of typically underconsumed nutrients. Increased family meal frequency may decrease risk of overweight or obesity in children and adolescents. Frequent family meals also may protect against eating disorders and negative health behaviors in adolescents and young adults. Psychosocial benefits include improved perceptions of family relationships. However, the benefits of having a family meal can be undermined if the family consumes fast food, watches television at the meal, or has a more chaotic atmosphere. Although these findings are intriguing, inconsistent research methodology and instrumentation and limited use of validation studies make comparisons between studies difficult. Future research should use consistent methodology, examine these associations across a wide range of ages, clarify the effects of the mealtime environment and feeding styles, and develop strategies to help families promote healthful mealtime habits.

Breastfeeding and mother-infant interactions

Abstract This study investigated the proposition that breastfeeding facilitates mother-infant interaction in a context beyond feeding. The free-play behaviors of 11 mother-infant pairs in which infants were currently breastfed were compared to 16 bottlefeeding dyads. Coded maternal behaviors included positive instances of play, touch, vocalizations and affect directed towards the infants, and positive vocalizations, reaching and affect by the infants to their mothers. Analyses revealed that currently breastfed mother-infant pairs displayed more maternal touch and less infant vocalizing, but more fussiness. However, breastfed males and bottlefed females exhibited the most optimal behaviors, suggesting a sex by feeding interaction effect. The results are discussed with respect to the developing mother-infant relationship.

Mothers and toddlers lunch together. The relation between observed and reported behavior.

Many factors are acknowledged as contributing to the current childhood obesity crisis, with the role of parenting style having recently come under scrutiny as researchers have begun to apply behavioral concepts like control and permissiveness to the context of feeding. In the present study, 20 mothers (10 overweight, 10 normal weight) and their 2-year-old offspring were observed eating a lunch under laboratory conditions. Mothers additionally provided demographic information and completed questionnaires regarding weight concerns and feeding styles. Overweight mothers were more concerned about their own weight relative to normal weight mothers but they showed no difference in their feeding behavior nor in their feeding behavior toward their children. Apart from maternal weight, however, aspects of maternal feeding style, namely observed and self-reported restriction and self-reported pressure, were associated with toddler Body Mass Index.

Early family mealtime experiences and eating attitudes in normal weight, underweight and overweight females.

The aim of this study was to examine young women’s recollections of family mealtimes in order to determine whether these memories may serve to differentiate those of normal weight from those who were underweight or overweight. A sample of 340 women selected on the basis of their enrollment in a college course completed the Childhood Family Mealtimes Questionnaire and the short form of the Eating Attitudes Test (EAT). The women were divided into under, normal and overweight groups on the basis of their body mass index (BMI). Two factors (appearance-weight control and emphasis on mother’s weight) were significantly higher among the overweight than the underweight women, and mealtime communication-based stress was highest among the underweight women. The use of family mealtimes as a window for understanding the development of eating disorders (ED) is discussed.

Feeding Method and Motor Activity in 3-Month-Old Human Infants

It is currently acknowledged that breast-fed and formula-fed infants exhibit different rates of physical growth. Little is known, however, about behavioral differences that may be attributable to early feeding method. In the present investigation, activity level in 3-mo.-old infants was examined by measuring motoric output in 40 breast-fed and 40 formula-fed infants. Maternal ratings of temperament did not differ across the two groups, but scores derived from the actometer in a laboratory setting showed breast-fed infants to be more active. Upper limb activity appeared to be particularly sensitive to feeding regimen. Possible explanations for this effect as well as implications of these results are discussed.

Diet, Activity and BMI in Preschool-Aged Children: Differences Across Settings

In the present study, children who attended either a University Preschool (UP) or a Head Start (HS) program were studied to determine if they differed in diet, activity, or body mass index (BMI) across settings. Dietary intake over 3 days and motor activity during a free-play period equivalent across settings were measured for 40 children age 4–5 years. Compared to the UP children, the HS children had a higher average food energy intake and lower motor activity. More than half of the HS children were determined to be at the 85th percentile or above on BMI for age and sex compared to little more than a third of the UP children. Apart from the socio-economic and racial/ethnic differences between the two groups of children, the physical environment may also have exerted an impact on activity levels, as the UP classroom and playground were twice as large in square feet in comparison to the HS facilities.

Behavioural Development in Chimpanzee (Pan troglodytes) and Human Newborns across the First Month of Life.

Comparisons among the behaviours of chimpanzee (Pan troglodytes) and human newborns on a standardised human neonatal assessment scale are reported for the infants at both 3 days and 1 month of age. Human infants scored significantly higher on the orientation cluster at both ages, and relative to the chimpanzee infants were lower in motoric maturity. With respect to the human standards employed, the two chimpanzee infants who were human-reared scored as optimally as did the human infants at 1 month, suggesting a differential impact of the care-giving environment on developing chimpanzee social behaviours.

Child Outdoor Physical Activity is Reduced by Prevalence of the Asian Tiger Mosquito, Aedes albopictus

We tested the hypothesis that day-biting mosquitoes contribute to child obesity by reducing opportunities for summer outdoor play. The influence of Asian tiger mosquito (Aedes albopictus) prevalence on child outdoor physical activity was compared in 2 matched urban communities, one treated for mosquito abatement and one untreated. More time was spent outdoors by children where abatement took place.

Developmental Organization, Stress, and Illness

The link between behavioral responsiveness to stress and subsequent health has been demonstrated in adults but not in infants and very young children. The ability of infants to suppress responding to acutely painful events was examined both as a function of neonatal status and as a predictor of incidence of illness at 18 to 24 months. Responding to stress in early infancy was predictive of later health but the nature of the relation depended on the maturity of the child.