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Try out PMC Labs and tell us what you think. Learn More. Eating behaviors evolve during the first years of life as biological and behavioral processes directed towards meeting requirements for health and growth. For the vast majority of human history, food scarcity has constituted a major threat to survival, and human eating behavior and child feeding practices have evolved in response to this threat.
Because infants are born into a wide variety of cultures and cuisines, they come equipped as young omnivores with a set of behavioral predispositions that allow them to learn to accept the foods made available to them. During historical conditions of scarcity, family life and resources were devoted to the procurement and preparation of foods, which are often low in energy, nutrients, and palatability.
In sharp contrast, today in non-Third World countries children's eating habits develop under unprecedented conditions of dietary abundance, where palatable, inexpensive, ready-to-eat foods are readily available. In this review, we describe factors shaping the development of children's food preferences and eating behaviors during the first years of life, in order to provide insight into how growing up in current conditions of dietary abundance can promote patterns of food intake which contribute to accelerated weight gain and overweight.
In particular, we focus on describing children's predispositions and parents' child feeding practices. We will see that the feeding practices that evolved across human history as effective parental responses to the threat of food scarcity, can, when combined with infants' unlearned preferences and predispositions, actually promote overeating and overweight in our current eating environments. In addition to the relatively recent changes in our eating environments, concurrent reductions in opportunities for physical activity undoubtedly also contribute to positive energy balance and obesity, but are outside the scope of this article.
The first five years of life are a time of rapid physical growth and change, and are the years when eating behaviors that can serve as a foundation for future eating patterns develop. During these early years, children are learning what, when, and how much to eat based on the transmission of cultural and familial beliefs, attitudes, and practices surrounding food and eating. Throughout, we focus on the vital role parents and caregivers play in structuring children's early experiences with food and eating, and describe how these experiences are linked to children's eating behavior and their weight status.
These days, food and drink are available in most venues of everyday life.
As ofthere werefood-service establishments in the United States and an additionalstores where food and beverages could be purchased. A typical American supermarket carries 45, items 2 and consumer portions served by restaurants and fast-food establishments are often double the size of current recommended USDA serving size.
In most families, women still have primary responsibility for feeding children. From tolabor force participation among mothers with children under eighteen years of age increased from forty-seven to seventy-one percent. Additionally, more women than men parent and feed their children without the assistance of a spouse: twenty-three percent of children under eighteen years of age live with their mother only.
One consequence of these trends is that young children are routinely fed by someone other than a parent. In fact, thirty-one percent of preschool-age children receive out-of-home childcare which includes mealtime care from a grandparent or other relative, and forty-one percent participate in organized childcare. Only fifty-five percent of married parents and forty-seven percent of single parents eat breakfast daily with their preschool-age.
A growing body of evidence suggests that the food choices a mother makes during her pregnancy may set the stage for an infant's later acceptance of solid foods. Amniotic fluid surrounds the fetus, maintaining fetal temperature, and is a rich source of sensory exposure for infants. Many flavors in the maternal diet appear to be present in amniotic fluid. Adult sensory panels have detected odors and compounds of garlic, 14 cumin, and curry 15 in the amniotic fluid of pregnant women ingesting oil of garlic capsules and spicy foods, respectively.
Because taste and smell are already functional during fetal life, and because the fetus regularly swallows amniotic fluid, the first experiences with flavor occur prior to birth. As we will see, familiarity plays a key role in the acquisition of food and flavor preferences. Breastfeeding is recommended as the optimal feeding method for the first six months of life, followed by the introduction of solids and continued breastfeeding for a minimum of one year. Specifically, Christopher Owen and colleagues conducted a systematic review of sixty-one studies, of which twenty-eight provided odds ratios to examine the influence of breastfeeding on obesity from infancy to adulthood.
They found that breastfeeding was associated with a reduced risk of obesity among infants, young children, older children, and adults with an unadjusted odds ratio of 0.
Of these twenty-eight studies, nine studies comprising more than 69, children were eligible for the meta-analysis. In one review of twenty-two high quality studies, fifteen found protective effects to be more consistently noted among school-aged children and adolescents than among younger children.
However, at this point, the mechanism s by which breastfeeding exerts protective effects are not understood. Specifically, breastfeeding is the ideal feeding method for the human infant and influences the developing anatomy and physiology of the gastrointestinal tract in ways that differ from formula feeding, such that breast-fed and formula-fed individuals may differ in the absorption and utilization of nutrients later in life.
The first involves the effects of breastfeeding on food acceptance and the second involves the developing controls of energy intake. The sensory properties of breast milk may facilitate the transition to the modified adult diet. Many flavors of the maternal diet appear in breast milk. For example, adult sensory panels can detect odors of garlic, 24 alcohol, 25 and vanilla 26 in milk samples of lactating women who ingested those flavors prior to providing milk samples.
Flavors in human milk influence infant consumption. For example, breast milk flavored with garlic 27 and vanilla 28 increased infant sucking time at the breast compared to breast milk without garlic or vanilla flavor. Mennella and colleagues also tested the hypothesis that experience with flavor in breast milk modifies the infants' acceptance and enjoyment of those foods in a sample of forty-five mothers and their babies that were randomly ased to one of three groups.
The first group drank carrot juice during pregnancy and water during lactation; group two drank water during pregnancy and carrot juice during lactation, and the control drank water during both conditions. These findings indicate that flavors in breast milk, which vary with the maternal diet, provide the infant with a changing flavor environment. This early flavor experience appears to facilitate the infant's acceptance of foods of the modified adult diet, especially those foods consumed by the mother during lactation.
There is limited evidence that these early differences in flavor experience provided by the breast and formula feeding also influence infants' subsequent acceptance of solid foods, especially those foods that might not otherwise be readily accepted, such as vegetables.
For example, Susan Sullivan and Leann Birch conducted a short term longitudinal study of nineteen breastfed and seventeen exclusively formula fed four- to six-month-old infants and their mothers to examine the influence of milk feeding regimen and repeated exposure on acceptance of their first pureed vegetable.
Participants were randomly ased to be repeatedly fed one vegetable, either pureed peas or green beans. revealed infant feeding regimen moderated the effects of repeated exposure; the initial intake of vegetables did not differ between breastfed and formula-fed infants, but breastfed infants increased their intake more rapidly over days than formula fed infants, and continued to consume ificantly more vegetables after ten exposures.
A second hypothesis regarding the protective effect of breastfeeding on later risk of overweight is that breastfeeding provides the infant with greater opportunity for self-regulation of intake. A limited body of evidence suggests that infants have some ability to self-regulate caloric intake by adjusting the volume of milk consumed, 32 although this can be influenced by maternal feeding practices.
In bottle feeding, the infant can obtain milk with less effort than from the breast, so the formula-fed infant is more passive in the feeding process and has fewer opportunities to control the amount consumed, making it easy to over-feed the infant. In contrast, the breastfed infant must take an active role in order to transfer milk from the breast.
The higher levels of maternal control that are possible with bottle feeding reduce infants' opportunities to control the amount consumed at a feeding. Whether and how infants exert control during feeding to regulate energy intake are not new questions. Clara Davis conducted seminal research in the late s and s, providing the first evidence of an unlearned ability to self-regulate energy intake in infancy.
In Davis' studies, infants and toddlers grew well and had few illnesses when given the opportunity to select and consume a variety of simply prepared foods at each meal. Inobservational data from Sharon Pearcey and John De Castro complemented these experimental findings, revealing that individual variability in energy consumed at meals among twelve-month-old infants was close to forty-seven percent, while variability in daily energy intake was seventeen percent.
The ability to regulate energy intake has also been described in preschool-age children. Children responded to covert manipulations in the energy content of foods served as first courses by adjusting their subsequent intake, such that their total energy intake for the meal and energy consumed over a thirty-hour period 40 was maintained across conditions in which low- or high-energy foods were provided as a first course.
Differences among preschool-age children in their ability to self-regulate energy intake have been associated with differences in weight status. For example, Susan Johnson and Leann Birch examined the influence of weight status on regulation of energy intake in seventy-seven three- to five-year-old children. Each child participated in two treatments, differing only in whether children received a low- or high-calorie preload of fruit flavored drinks of equal volume before lunch. After twenty minutes, children self-selected intake from a familiar lunch menus i.
They found that children who showed little evidence of adjusting their lunch intake in response to the energy differences in the prelo were ificantly heavier. Data were used from two separate lunches which differed in whether a low- or high-energy preload drink was consumed prior to lunch. Again, after a brief delay, participants ate a self-selected lunch i. indicated substantial individual differences in the extent to which girls adjusted their energy intake at lunch in response to the differences in preload energy content.
On average the girls only compensated for about half of the energy in the prelo. In this case, greater maternal restriction in feeding was associated with poorer compensation and higher weight status in daughters. Infants do not have to learn preferences for the basic tastes sweet, salty, sour, bitter, and umami. Rather, they are predisposed to pleasing flavors. Shortly after birth infants express preferences for sweet tastes and reject those that are sour and bitter. In general, sweet foods such as fruits, flavored yogurts, and juices are readily accepted by infants, while foods such as vegetables, which are not sweet, and may contain bitter components, are initially rejected.
Laboratory studies have confirmed that young children readily form preferences for flavors associated with energy rich foods. Alternatively, children's acceptance of foods that have less intrinsic hedonic appeal to children such as vegetables are shaped by their experience with those foods. Children decide their food likes and dislikes by eating, and associating food flavors with the social contexts and the physiological consequences of consumption.
The tendency for children to initially reject novel foods is often just a case of neophobia. Several studies have demonstrated that children's preferences for and acceptance of new foods are enhanced with repeated exposure to those foods in a non-coercive setting.
New foods may need to be offered to preschool-aged children ten to sixteen times before acceptance occurs. At the same time, simply offering new foods will not necessarily produce liking; having children taste new foods is a necessary part of the process. During the first year of life, eating patterns undergo rapid evolution.
Initially, infants obtain all nutrition from a single fluid source i. By the end of the first year, however, the infant has moved to a modified meal and snack pattern, consuming many foods found in their culture's adult diet. The American Academy of Pediatrics AAP recommends breastfeeding for the first four to six months of life, followed by the introduction of complementary foods once the child is developmentally ready.
Only four located studies examined the association between the timing of complementary food introduction and weight gain in longitudinal studies. Two of these studies linked the early introduction of solid foods and obesity at twelve months 52 and eighteen months 53 of age, independent of breastfeeding. However, the other studies, using similar des, failed to note associations between the early introduction of solid foods and childhood obesity at twenty-four months 54 and seven years of age.
from a recent survey, the Feeding Infants and Toddlers Study, which provides data on the dietary patterns of 3, infants and toddler four to twenty-four months of age, has also raised concerns regarding excessive energy intake as well as the quality of young children's diets. also revealed that eighteen to thirty-three percent of infants and toddlers consumed no servings of vegetables, and twenty-three and thirty-three percent consumed no fruits. Moreover, fewer than ten percent of infants and toddlers consumed dark green, leafy vegetables. The large amounts of fruit juice and sweetened beverages that begin to appear in young children's diets have also been cause for concern.
The AAP recommends no more than four to six ounces a day of fruit juice for children one- to six-years old. Alternatively, Jean Welsch and colleagues used a retrospective longitudinal de to evaluate juice intake and the persistence of overweight among two- to three-year-old children. Consumption of sweetened beverages i. Parents powerfully shape children's early experiences with food and eating, providing both genes and environments for children.
Children's eating patterns develop in the early social interactions surrounding feeding. As young omnivores, they are ready to learn to eat the foods of their culture's adult diet, and their ability to learn to accept a wide range of foods is remarkable, especially given the diversity of dietary patterns across cultural groups. Several decades of research inside and outside of the laboratory have revealed that, as in other areas of children's development, caregivers act as powerful socialization agents.
Studies conducted outside the laboratory support the notion that children's preference and intake patterns are largely a reflection of the foods that become familiar to them. Research indicates that the extent to which fruits and vegetables are present and readily available and accessible in the home correlates positively with the level of consumption in school-age children. Furthermore, the availability of fruits and vegetables was a moderating variable for intake by both parents and children.
In a study of beverage intake among girls during middle childhood, milk consumption among girls almost always or always served milk at meals and snacks was two times higher than it was for girls rarely or never served milk. Similarities in milk intake quantities among mothers and daughters were also attributable to the extent that milk was served at meals. Children's intake of particular foods is influenced not only by the types of foods present in the home but also by the amount of those foods available to them.
Recent laboratory studies provide causal evidence that large food portions promote greater energy intake by children as young as two years of age. As a result, energy intake was nine to fifteen percent higher at meals during which larger portions were served. Adults, like children, eat more when served large portions.
Evidence from laboratory studies suggests that larger portions served to consumers at restaurants, in convenience and grocery stores, and in other retail settings are driving increases in the average size of portions consumed both at home and away from home, 73 as well as increasing the daily energy intake of children.
Children learn about food through the direct experience of eating and by observing the eating behavior of others. Leann Birch found that the selection and consumption of vegetables by preschool-age children were influenced by the choices of their peers. For example, Helen Hendy and Bryan Raudenbush found that children's intake of a novel food increased at those meals during which they observed a teacher enthusiastically consuming the food. Interestingly, enthusiastic modeling by a teacher was not as effective when children were seated with peers who exhibited different food preferences than did their teachers.
Studies conducted outside the laboratory also provide indirect evidence for the role of social modeling. For example, low-income adolescent girls who reported seeing their fathers consume milk had higher calcium intakes than did those girls who did not see their fathers drink milk. Parenting, by definition, involves the task of care and feeding one's children.
Subsequently, child feeding practices have evolved as parental responses to perceived environmental threats to children's well being. Feeding practices developed to address these threats have been passed from one generation to the next, and have become traditional practices routinely used by parents without question. Traditional feeding practices used with infants and young children include feeding children frequently and quickly in response to distress, offering foods deed especially for infants and young children, offering preferred foods if possible, and encouraging children to eat as much as possible when food is available, often involving the use of coercion and force feeding.
There are, of course, differences across cultures in the specifics of these practices and in the particular foods offered to children. There are also differences within cultures among parents' feeding practices. These differences are caused by cultural differences among parents and by their goals for their children. In addition, parents' feeding practices are influenced by children's individual characteristics, including age, sex, weight status, and eating behavior. Parenting practices and parent-child interaction during feeding vary in the degree to which children are allowed some degree of autonomy in eating.Text individual adult Cowarts Alabama right now
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