Childhood obesity

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These children vary in their proportion of body fat.
These children vary in their proportion of body fat.

Childhood obesity is a medical condition that affects children. It is characterized by a weight well above the mean for their height and age and a body mass index well above the norm. Childhood obesity is considered by many to be an "epidemic" in Western countries, in particular, the United States, United Kingdom and Australia.[citation needed]

Contents

[edit] Rate

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Over the last decades, there has been an increase to a current level of 20% of American children who are currently considered obese.[1][2] In 2008, the rate of overweight and obese children in the United States was 32%, and had stopped climbing.[3]

[edit] Causes

Poor eating habits can lead to obesity, even at a young age.
Poor eating habits can lead to obesity, even at a young age.

As with many conditions, childhood obesity can be brought on by a range of factors, often in combination.[4][5][6][7][8]

[edit] Eating habits

Childhood obesity results from poor eating habits. In a study of 99 children, between 11 and 16 years, professional dietitians put the children on a regulated diet program for a nine month period, leading to an average weight loss of 66 pounds. However, during the two year follow-up, dieticians discovered that intake of daily calories had increased by 391 calories, leading to weight gain in the subjects.[9] Soft drink consumption may also be an unhealthy eating/drinking leading to childhood obesity. In a study of 548 children during a 19 month period, researchers examined the correlation of soft drink consumption to childhood obesity. They discovered children were 1.6 times more likely to be obese for every soft drink consumed each day.[10]

Daily consumption of fast food and junk food has dominated over healthy food choices. Researchers provided a lunchtime survey for a one year period to 1681 children, ages five to 12 years old. They discovered that although 68% of the children did have fruit in their lunchboxes, 90% of the children had junk food in their lunch boxes.[11]

In another study an FFFRU (Frequency of Fast Food Restaurant Use) survey was given to 4,746 students, in grades seven through 12, and researchers discovered that 75% of students had eaten at a fast food restaurant in the past week.[12] Eating out on a regular basis has resulted in child weight gain. Researchers studied the dietary records of 101 healthy girls, from ages 8–19 years over a one year period and a four to 10 year follow up. They discovered that girls who ate quick service food two or more times a week had a BMI z score (provides comparative measure of body fat accustomed for age) of 0.82, compared to those who ate it less than twice a week, with a BMI z score of 0.2–0.28.[13]

Neglecting to eat certain meals completely can also create weight gain.[dubious – discuss] Children who fail to eat breakfast could face potential weight gain. Researchers provided a breakfast questionnaire to 14,000 children over a three year period and discovered that 7.35% more children who never ate breakfast were overweight, compared to overweight children who ate breakfast every day.[14]

Overall, as American society has shifted and changed, so too have the eating habits of the American people. For a society that is constantly on-the-go, fast food meals have become dominate in the lifestyles of most American families as more traditional, healthy meals have taken a backseat in our fast-paced lives.

[edit] Family influence

Childrens' food choices are also influenced by family meals. Researchers provided a household eating questionnaire to 18,177 children, ranging in ages 11–21, and discovered that four out of five parents let their children make their own food decisions. They also discovered that compared to adolescents who ate three or fewer meals per week, those who ate four to five family meals per week were 19% less likely to report poor consumption of vegetables, 22% less likely to report poor consumption of fruits, and 19% less likely to report poor consumption of dairy foods. Adolescents who ate six to seven family meals per week, compared to those who ate three or fewer family meals per week, were 38% less likely to report poor consumption of vegetables, 31% less likely to report poor consumption of fruits, and 27% less likely to report poor consumption of dairy foods.[15]

Depending on the child's environment and parental status, a child may be more inclined to eat more food than needed if a parent is not present to monitor the consumption of meals or snacks. If a parent is present, then it is more likely that a child will refrain from eating more than they should, possibly to avoid discussing the issue of their weight or size if they are in fact overweight.[citation needed]

It has also been suggested that children with parents that are divorced and live in separate housing structures are more likely to put on more weight than if both parents are present in the consumption of one meal. This may be because children may be fed at least two meals at a time, if the other parent was not aware that their child had already had a meal or snack. If the child is suffering from depression due to their parent's divorce, this may result in an increase in appetite because of their feelings.[citations needed]

[edit] Physical activity

An obese child whose lack of exercise and consumption of excessive amounts of carbohydrates and fats contributes to his overall obesity.
An obese child whose lack of exercise and consumption of excessive amounts of carbohydrates and fats contributes to his overall obesity.

Physical inactivity of children has also shown to be a serious cause, and children who fail to engage in regular physical activity are at greater risk of obesity. Researchers studied the physical activity of 133 children over a three week period using an accelerometer to measure each child's level of physical activity. They discovered the obese children were 35% less active on school days and 65% less active on weekends compared to non-obese children.

Physical inactivity as a child could result in physical inactivity as an adult. In a fitness survey of 6,000 adults, researchers discovered that 25% of those who were considered active at ages 14 to 19 were also active adults, compared to 2% of those who were inactive at ages 14 to 19, who were now said to be active adults.[16] Staying physically inactive leaves unused energy in the body, most of which is stored as fat. Researchers studied 16 men over a 14 day period and fed them 50% more of their energy required every day through fats and carbohydrates. They discovered that carbohydrate overfeeding produced 75–85% excess energy being stored as body fat and fat overfeeding produced 90–95% storage of excess energy as body fat.[17]

Many children fail to exercise because they are spending time doing stationary activities. TV and other technology may be large factors of physically inactive children. Researchers provided a technology questionnaire to 4,561 children, ages 14, 16, and 18. They discovered children were 21.5% more likely to be overweight when watching 4+ hours of TV per day, 4.5% more likely to be overweight when using a computer one or more hours per day, and unaffected by potential weight gain from playing video games.[17]

Technological activities are not the only household influences of childhood obesity. Low-income households can affect a child's tendency to gain weight. Over a three week period researchers studied the relationship of socioeconomic status (SES) to body composition in 194 children, ages 11–12. They measured weight, waist girth, stretch stature, skinfolds, physical activity, TV viewing, and SES; researchers discovered clear SES inclines to upper class children compared to the lower class children.[18]

[edit] Biological factors

Children face many biological factors that may result in obesity. A child's weight may be influenced when he/she is only an infant. Researchers did a cohort study on 19,397 babies, from their birth until age seven and discovered that fat babies at four months were 1.38 times more likely to be overweight at seven years old compared to normal weight babies. Fat babies at the age of one were 1.17 times more likely to be overweight at age seven compared to normal weight babies.[19]

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Genetic causes have been investigated as a cause of childhood obesity. Researchers studied 4997 children, ages 5–7, and 2631 parents over a five year period to examine the hereditary correlation of obesity; parents were given a family nutrition questionnaire. Researchers discovered 50% of the children with obese mothers were obese or overweight and 40.1% of children with obese fathers were obese or overweight. However, 41.95% of children with normal weight mothers were obese or overweight and 34.25% of children with normal weight fathers were obese or overweight.[20] Studies have also suggested that parental obesity may not be passed down to children. Researchers provided a parent questionnaire to the parents of 85 children, with the children being 36 months old. They discovered that girls were only 0.14 times likely to have similar BMI scores to parents and boys were only 0.48 times likely to have similar BMI scores to parents. This study demonstrates that there is no significant correlation between a parents' obestity and that of their children.[21]

Other studies estimate that the effect of genes account for 90-95 percent of the percent body fat (PBF) in children, while the remaining 5-10 percent is attributed to learned the behavior.[citation needed]

While there is general acceptance that hereditary conditions might incline to human obesity, it is often assumed that such factors would affect metabolic rate or the selective transforming of surplus of calories into fat.

Genetic factors are engaged in the regulation of child body weight and in determining individual reactions to environmental factors such as food, rest and exercise. Scientists have discovered a close connection between levels of leptin, a protein which controls appetite and the rate at which calories are burned, and the body fat.[citation needed] That means leptin is an important regulator of energy balance in humans, helping the body to keep its weight stable. As in many obese children tests have revealed very low levels of blood leptin, there are opinion that obesity, especially its severe forms, could be treated by correcting this congenital leptin deficiency.

There are also and contraire opinions suggesting that leptin could not be a cure for the overweight. They are partly linked with studies of adopted children revealing that learned eating and activity behavior are more important that genetic inheritance.[citation needed]

[edit] Developmental factors and illnesses

Children can have various developmental factors of the body that may result in obesity. A child's body growth pattern may influence his/her tendency to gain weight. Researchers measured the standard deviation (SD [weight and length]) scores in a cohort study of 848 babies. They found that infants who had an SD score above 0.67 had catch up growth (they were less likely to be overweight) compared to infants who had less than a 0.67 SD score (they were more likely to gain weight).[22]

Cushing's syndrome (condition in which body contains excess amounts of cortisol) may influence childhood obesity as well. Researchers analyzed two isoforms (proteins that have the same purpose as other proteins, but are programmed by different genes) in the cells of 16 adults undergoing abdominal surgery. They discovered that one type of isoform created oxo-reductase activity (the alteration of cortisone to cortisol) and this activity increased 127.5 pmol mg sup when the other type of isoform was treated with cortisol and insulin. The activity of the cortisol and insulin can possibly activate Cushing's syndrome.[23]

Hypothyroidism is a hormonal cause of obesity, but it does not significantly affect obese people who have it more than obese people who do not have it. In a comparison of 108 obese patients with hypothyroidism to 131 obese patients without hypothyroidism, researchers discovered that those with hypothyroidism had only 0.077 points more on the caloric intake scale than did those without hypothyroidism.[24]

[edit] Behavioral factors

Childhood obesity may also be caused by various behavioral factors. Behavioral factors, such as boredom, sadness, and anxiety may influence a child's health. Researchers surveyed 1,520 children, ages 9–10, with a four year follow up and discovered a positive correlation between obesity and low self esteem in the four year follow up. They also discovered that decreased self esteem led to 19% of obese children feeling sad, 48% of them feeling bored, and 21% of them feeling nervous. In comparison, 8% of normal weight children felt sad, 42% of them felt bored, and 12% of them felt nervous.[25] Stress can influence a child's eating habits. Researchers tested the stress inventory of 28 college females and discovered that those who were binge eating had a mean of 29.65 points on the perceived stress scale, compared to the control group who had a mean of 15.19 points.[26] This evidence may demonstrate a link between eating and stress.

[edit] Psychological factors

Psychological factors also influence childhood obesity. Researchers did a health investigation of 496 girls, ages 11–15 with a four year follow up. They discovered four significant psychological factors to the girls' obesity: dietary restraint, compensatory behaviors, depressive symptoms, and perceived parental obesity. The odds ratios (OR's) these had with obesity were 3.16, 1.35, 2.32, and 3.97.[27]

Feelings of depression can cause a child to overeat. Researchers provided an in-home interview to 9,374 adolescents, in grades seven through 12 and discovered that there was not a direct correlation with children eating in response to depression. Of all the obese adolescents, 8.2% had said to be depressed, compared to 8.9% of the non-obese adolescents who said they were depressed.[28] Antidepressants, however, seem to have very little influence on childhood obesity. Researchers provided a depression questionnaire to 487 overweight/obese subjects and found that 7% of those with low depression symptoms were using antidepressants and had an average BMI score of 44.3, 27% of those with moderate depression symptoms were using antidepressants and had an average BMI score of 44.7, and 31% of those with major depression symptoms were using antidepressants and had an average BMI score of 44.2.[29]

[edit] Lack of sleep

A Harvard study completed in 2008 found that the amount of sleep infants and toddlers received directly impacted[dubious – discuss] rates of obesity. Specifically the study found that infants and toddlers that received less than 12 hours of sleep each day were at an increased risk for becoming overweight by the time they reached preschool age.[30] The study recorded sleep patterns in infants from 6 months of age until they reached the age of 2.

[edit] Complications

A morbidly obese teenager whose attribution of poor diet, high caloric intake, and lack of exercise has caused excessive amounts of fat to be stored primarily in the chest and stomach, and evenly distributed elsewhere as well.
A morbidly obese teenager whose attribution of poor diet, high caloric intake, and lack of exercise has caused excessive amounts of fat to be stored primarily in the chest and stomach, and evenly distributed elsewhere as well.

Without a change in diet or exercise patterns, childhood obesity can lead to life-threatening conditions including diabetes, high blood pressure, heart disease, sleep problems, cancer, and other disorders.[31][32] Some of the other disorders would include liver disease, early puberty or menarche, eating disorders such as anorexia and blumia, skin infections, and asthma and other respiratory problems. [3] Studies have shown that overweight children are more likely to grow up to be overweight adults.[33]

Obese children often suffer from teasing amongst their peers.[34][35] Some are even harassed or discriminated against by their own family.[36] Stereotypes abound and may lead to low self esteem and depression.[37]

[edit] Medications

Just as recently as 2005, there were no medications available to treat child obesity that were approved by FDA. Two prescription weight-loss drugs are available for adolescents: sibutramine (Meridia) and orlistat (Xenical). Sibutramine, which is approved for adolescents older than 16, alters the brain's chemistry to make the body feel fuller more quickly. Orlistat, which is approved for adolescents older than 12, prevents the absorption of fat in the intestines. The Food and Drug Administration has approved a reduced-strength over-the-counter (nonprescription) version of orlistat (Alli). Though readily available in pharmacies and drugstores, Alli is not approved for children or teenagers under age 18.[4]

[edit] Studies

A study of 1800 children aged 2 to 12 in Colac, Australia tested a program of restricted diet (no carbonated drinks or sweets) and increased exercise. Interim results included a 68% increase in after school activity programs, 21% reduction in television viewing, and an average of 1 kg weight reduction compared to a control group.[38]

A survey carried out by the American Obesity Association into parental attitudes towards their children's weight showed the majority of parents think that recess should not be reduced or replaced. Almost 30% said that they were concerned with their child's weight. 35% of parents thought that their child's school was not teaching them enough about childhood obesity, and over 5% thought that childhood obesity was the greatest risk to their child's long term health.[39]

Although obesity is more common in girls,[40] it is more apparent in boys who tend to accumulate fat in the stomach area, and, to a lesser extent, the back and chest.

A Northwestern University study indicates that inadequate sleep has a negative impact on a child's performance in school, their emotional and social welfare, and increases their risk of being overweight. This study was the first nationally represented, longitudinal investigation of the correlation between sleep, Body Mass Index (BMI) and overweight status in children between the ages of 3 and 18. The study found that an extra hour of sleep lowered the children's risk of being overweight from 36% to 30%, while it lessened older children's risk from 34% to 30%.[41]

[edit] See also

[edit] References

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  30. ^ [1]
  31. ^ [2][dead link]
  32. ^ Childhood Obesity
  33. ^ Childhood Obesity
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  35. ^ Obesity.Org
  36. ^ Obesity.Org
  37. ^ SRTS Guide: Health Risks
  38. ^ "Obesity study bears fruit", The Age, 24 August 2006.
  39. ^ Survey on parents' perceptions of their children's weight, American Obesity Association. August, 2000. Retrieved 2006-11-21
  40. ^ Childhood Obesity
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[edit] External links