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Influences On Normal Physical Essay Research Paper

Physical growth in early childhood is partially easy to measure and

gives an idea of how children normally develop during this period. The

average child in North America is less than three feet tall at two years of

age. Physical growth contains no discrete stages, plateaus, or qualitative

changes. Large differences may develop between individual children and

among groups of children. Sometimes these differences affect the

psychological development of young children. These differences create a

nice variety among children.

Most dimensions of growth are influenced by the child’s genetic

background. Also, races and ethnic backgrounds around the world differ

in growth patterns. Nutrition can affect growth, but it does not override

genetic factors.

One factor in the cause of slow growth is malnutrition. Malnutrition

can start as early as pregnancy. Low birth weight babies have an

increased risk of infection and death during the first few weeks of life.

Food-deprived children carry a greater risk of neurological deficiencies

that result in poor vision, impaired educational attainment, and cerebral

problems. Such children are also more prone to diseases such as malaria,

respiratory tract infections or pneumonia. The illnesses of malnourished

children can cause more lasting damage than in a healthy child. The

destructive conjunction between low food intake and disease is magnified

at the level of the hungry child. There is evidence, according to The

Journal of Nutrition, that an estimated 50 percent of disease-related

mortality among infants could be avoided if infant malnutrition were

eradicated. It has also been shown that low birth- weight is associated

with increased prevalence of diseases such as stroke, heart disease and

diabetes in adult life. Most damage during the first few years of life

cannot easily be undone.

There are many reasons why some children never reach normal

height. Some causes of short stature are well understood and can be

corrected, but most are subjects of ongoing research. Achondroplasia is

the most common growth defect in which abnormal body proportions are

present. Achondroplasia is a genetic disorder of bone growth. It affects

about one in every 26,000 births. It occurs in all races and in both

sexes. It is one of the oldest recorded birth defects found as far back as

Egyptian art. A child with achondroplasia has a relatively normal torso

but short arms and legs. People sometimes think the child is mentally

retarded because they are slow to sit, stand, and walk alone. In most

cases, however, a child with achondroplasia has normal intelligence.

Children with achondroplasia occasionally die suddenly in infancy or early

childhood. These deaths usually occur during sleep and are thought to

result from compression of the upper end of the spinal cord, which can

interfere with breathing. This disease is caused by an abnormal gene.

The discovery of the gene allowed the development of highly accurate

prenatal tests that can diagnose or rule out achondroplasia. There is

currently no way to normalize skeletal development of children with

achondroplasia, so there is no cure. Growth hormone treatments, which

increase height in some forms of short stature, do not substantially

increase the height of children with achondroplasia. There is no way to

prevent the majority of cases of achondroplasia, since these births result

from totally unexpected gene mutations in unaffected parents.

One treatment available for children is known as growth hormone

therapy. The policy governing the use of growth hormone (GH) therapy

has shifted from treating only those children with classic growth hormone

deficiency to treating short children to improve their psycho social

functioning. This has caused quite a controversy. Parents have described

shorter boys as less socially competent and having more behavioral

problems than that of the normal sample. Shorter boys describe

themselves as less socially active but not having more behavioral

problems than that of the normal group. This is according to a study

conducted by the Children’s Hospital of Buffalo and the State University

of New York at Buffalo. The researchers conclude growth hormone

therapy should not be administered routinely to all short children for the

purpose of improving their psychological health. They urge that

physicians consider both a child’s short stature and psycho social

functioning before making a referral for growth hormone therapy.

Another factor in the growth of children is their change of appetite.

Young preschoolers may eat less than they did as a toddler. This is also

when they will become more selective and choosy with the foods they

eat. These changes are normal and result from the slowing down of

growth after infancy. Preschool children simply do not need as many

calories as they did after birth. Children’s food preferences are influenced

by the adult models around them. Preschoolers tend to like the same

foods as their parents and other important adults in their lives.

Variations in growth can result from cultural and psychological

factors. Failure to thrive is defined in the class textbook as a condition in

which an infant seems seriously delayed in physical growth and is

noticeably apathetic in behavior. This condition may result from situations

that interfere with normal positive relationships between parent and child,

especially during infancy or the early preschool period. The result is a

deprived relationship that may lead the child to eat poorly or be plagued

by constant anxiety. The nervousness can interfere with sleep or the

production of growth hormones. If failure to thrive has not persisted for

too long, it usually can be reversed in the short run through special

nutritional and medical intervention to help the child regain strength and

begin growing normally again.

There are many factors that can result in slow growth in children.

Between the ages of two and five, growth slows down and children take

on more adult bodily proportions. Usually growth is rather smooth during

the preschool period. Genetic and ethnic backgrounds affect its overall

rate, as do the quality of nutrition and children’s experiences with illness.

Children’s appetites are often smaller in the preschool years than in

infancy, and preschoolers become more selective about their food

preferences. If children fall behind in growth because of poor nutrition or

hormonal deficiencies, they often can achieve catch-up growth if slow

growth has not been too severe or prolonged. A few children suffer from

failure to thrive, a condition marked by reduced physical growth, possibly

as a result of family stress and conflict. Bibliography

Achondroplasia. Public Health Education Information Sheet.

Http://www.noah.cuny.edu/pregnancy/march_of_dimes/birth_de

fects/achondro.html.

Byers, T. 1995. The Emergence of Chronic Diseases in Developing

Countries. SCN News 13: 14-19; Golden, M. H. N. 1995. Specific

deficiencies versus growth failure. SCN News 12:10-14.

Growth Hormone: Not for All Short Children. Medical Sciences

Bulletin, Pharmaceutical Information Associates, Ltd.

Http://www.pharmingo.com/pubs/msb/grhorm.html.

Mason, J. B. 1990. Malnutrition and Infection. SCN News. 5:

2o21; UN Administrative Committee on Coordination-Sub Committee

on Nutrition (ACC/SCN). 1995. Maternal Nutrition and health: A

Summary of Research on Birth weight. Maternal Nutrition and Health 14

(1/2): 14-17.

Pelletier, D. 1995. The Effects of Malnutrition on Child

Mortality in Developing Countries. Bulletin of the World Heath

Organization 73 (4); Pelletier, D. 1994. The Relationship between Child

Anthropometry and Mortality in Developing Countries. The Journal of

Nutrition. Supplement 124 (1OS).

Pollitt, E. 1995. Nutrition in Early Life and the Fulfilment of

Intellectual Potential. The Journal of Nutrition. Supplement 125 (4S):

1111S- 1118S.

Seifert, Kelvin L. and Robert J. Hoffnung. Child and Adolescent

Development. 1997, Chapter 8, pages 236-244.




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