Each child is an unique individual whose heredity and environment shape the course of his or her life. Woven into the daily life are aspects of food and nutrition. What childhood memories of food do you have? Are these memories healthy or unhealthy?
Foods and their nutrients are essential to life. In the beginning years of life an infant’s nutritional health depends on the family unit. Parents must have knowledge of the changing food needs of the child and must also have sufficient resources to provide food, shelter, and clothing for the family. Equally important, parents create the cultural and psychological environment that influences the development of food habits, setting the patterns for later years.
During the preschool years some children depend solely on family caregivers for their nutritional needs. For other preschooler children the responsibility for meeting nutritional needs is shared by the family and others, such as caregivers in child-care centers and babysitters. The child entering school becomes influenced by teachers and peers, and learns to broaden his or her experiences with food. For many people, the adolescent years often are turbulent as the teenager seeks independence and freedom from adult rules and standards.
In this research, I will focus on nutrition, in retrospect to growth and development in infants, preschoolers, school children and adolescents.
Infants vary widely in their growth patterns, so it would be unwise to compare one infant with another. Yet there is value in being familiar with typical patterns of growth and development. At birth, the fetus makes an abrupt transition to life outside the uterus. Adaptation to extrauterine life is one of the most important steps in the life cycle because, for many systems in the body, birth precipitates dramatic changes in function. The respiratory system undergoes major changes as the newborn’s lungs fill with air during the first breath, and gas exchange across the pulmonary circulation abruptly replaces placental transfer.
Similarly, birth triggers a major transformation in nutritional pathways and metabolism of the newborn. At a time when nutritional needs are high (per unit body weight higher than at any other time after birth) the newborn must abruptly begin to swallow, digest, and absorb a variety of complex proteins, lipids, and carbohydrates. No longer are readily available simple substrates provided by the mother via the placenta.
The newborn begins to convert substrates-protein to glucose, glucose to fat, and must adapt to a discontinuous supply of nutrients. Glycogen stored during feedings must be converted to glucose to support energy needs between feedings. Adding further to the vulnerability of the newborn period, many of the digestive and absorptive functions of the newborn are incompletely developed (Schmitz, 1991).
To ease the transition through this turbulent period, the newborn needs to be provided with easily digestible and bioavailable nutrition in the form of breast milk or infant formula. The infant depends on a diet of closely regulated composition and does not achieve nutritional independence until weaning.
Here I will focus on the physical growth during infancy. Physical growth is more rapid during the first few months postpartum than at any other time after birth. In the first three months, a healthy infant’s birth length increases by 20% and, by the end of the first year, by 50%. By the end of infancy (2 year old) the average child has already achieved half the ultimate adult height. Although the rate of growth is remarkably high during infancy, it is actually decelerating from the extremely high rates achieved during growth in utero. ( ) A healthy infant gains about 25 cm during the first year, but growth rate slows during the second year. From age 1 to 2 years the average age height increases is 1-13cm.
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