Childhood obesity

Dr Prashant Pruthi,
MD – (Paediatrics)

How do I know if
my child is obese?
Your doctor will use a chart to find out your child’s ideal weight. If your child is heavier than 95% of other children who are the same age and height, he or she is considered to be overweight. Between 5-25 per cent of children and teenagers are obese. Excess weight has both immediate and long-term consequences and this issue demands serious attention.

Obesity is defined by the presence of excess adipose tissue. A person whose body weight is in excess of a standard weight is termed overweight. The World Health Organisation (WHO) has recommended the use of Body Mass Index (BMI) for age as the indicator of a child being overweight or obese. BMI is an indirect measure of body fat. It is defined as weight (in kg) divided by height (in metre squared) (kg/m2). A child having a BMI more than 95% of other children who are of the same age and sex or greater than 30kg/m2 is considered obese

Contributors of childhood obesity
There is no single cause of childhood obesity; rather, it is a complex interaction of many variables. Contributing factors include genetics, behaviour, environment, and certain socio-demographics.

Genetics – Certain genetic characteristics may increase an individual’s susceptibility to excess body weight, however, there are many genes involved and a strong interaction between genetics and environment influences the degree of excess body weight. It has been shown that obesity tends to run in families, suggesting a genetic link. In some cases, parental obesity is a stronger predictor of childhood obesity than the child’s current weight status alone.

Behaviour – Weight gain occurs as a result of energy imbalance, specifically when a child consumes more calories than the child uses. Several behavior patterns can contribute to weight gain including nutrition, physical activity, and sedentary behaviour.

Nutrition – An increase in availability and consumption of high-calorie convenience foods and beverages, more meals eaten away from home, fewer family meals, and greater portion sizes may all contribute to childhood obesity. Further, many children’s diets does not meet nutrition guidelines. For example, only 8 per cent of children in a study, ate vegetables three or more times per day as recommended by the US Department of Agriculture.

Physical Activity – Decreased opportunities and participation in physical activity is another behavioral factor that contributes to overweight children. Being physically active not only has positive effects on body weight, but also on blood pressure and bone strength. It has also been shown that physically active children are more likely to remain physically active into adolescence and adulthood. Children may spend less time being physically active during school as well as at home. School physical education programmes have decreased and children are not walking to school and are doing household chores less frequently.

Screen time – While physical activity levels have decreased, sedentary behaviour, such as watching television, playing on the computer and with video games has increased. Sedentary behaviour, and specifically television viewing, may replace time that children spend on physical activities and contribute to increased calorie consumption through excessive snacking and eating meals in front of the television. It also influences children to choose high-calorie, low-nutrient foods through exposure to food advertisements, and decreases children’s metabolic rate.

Environment – There are a variety of environmental factors that can potentially contribute to childhood obesity, including the home, childcare settings, school, and the community. The school and community settings are other environments where children learn about eating and physical activity habits. It is becoming increasingly important for all children to have access to healthful food choices and safe physical activity opportunities. Advocating for innovative school nutrition and physical activity programs as well as ensuring that there are well-lit sidewalks, bike paths, and parks in the community can all help to shift towards a more healthful environment for our children.

Socio-Demographics – Certain ethnic minority and socioeconomic populations have increased rates of childhood obesity. Low-income families face numerous barriers including food insecurity, lack of safe places for physical activity, and lack of consistent access to healthful food choices, especially fruits, vegetables and lean protein.

Consequences of childhood obesity
Overweight children and adolescents are at an increased risk for several health complications. During their youth, for example, they are more likely to exhibit risk factors for cardiovascular disease including high blood pressure, high cholesterol, and diabetes compared with normal weight individuals.  Additional health complications associated with overweight children include sleep apnea, asthma, and liver damage. Further, overweight children and adolescents are more likely to become obese adults. Finally, childhood obesity has psychological and emotional consequences. Overweight children are at an increased risk of being teased and bullied, low self-esteem, and poor body image.

Treatment of childhood obesity
Obesity treatment programmes for children and adolescents rarely have weight loss as a goal. Rather, the aim is to slow or halt weight gain so the child will grow into his or her ideal body weight over a period of months to years. It is estimated that for every 20 per cent excess of ideal body weight, the child will need one and one-half years of weight maintenance to attain ideal body weight. Early and appropriate intervention is particularly valuable. Childhood eating and exercise habits are more easily modified than adult habits .The three recommended forms of intervention include:

Physical activity
Adopting a formal exercise programme, or simply becoming more active, is valuable to burn fat, increase energy expenditure, and maintain lost weight. Most studies of children have not shown exercise to be a successful strategy for weight loss unless coupled with another intervention, such as nutrition education or behaviour modification. However, exercise has additional health benefits. Even when a child’s body weight and fat did not change following 50 minutes of aerobic exercise three times per week, blood lipid profiles and blood pressure did improve. 

Diet management
Fasting or extreme caloric restriction is not advisable for children. Not only is this approach psychologically stressful, but it may adversely affect growth and the child’s perception of “normal” eating. Balanced diets with moderate caloric restriction, especially reduced dietary fat, have been used successfully in treating obesity. Nutrition education may be necessary. Diet management coupled with exercise is an effective treatment for childhood obesity 

Behaviour modification
Many behavioural strategies used with adults have been successfully applied to children and adolescents: self-monitoring and recording food intake and physical activity, slowing the rate of eating, limiting the time and place of eating, and using rewards and incentives for desirable behaviours.

Particularly effective are behaviourally based treatments that include parents used problem-solving exercises in a parent-child behavioural programme and found children in the problem-solving group, but not those in the behavioural treatment-only group, significantly reduced percent overweight and maintained reduced weight for six months. Problem-solving training involved identifying possible weight-control problems and, as a group, discussing solutions.

Prevention of childhood obesity
Obesity is easier to prevent than to treat, and prevention focuses in large measure on parent education. In infancy, parent education should centre on promotion of breastfeeding, recognition of signals of satiety, and delayed introduction of solid foods. In early childhood, education should include proper nutrition, selection of low-fat snacks, good exercise/activity habits, and monitoring of television viewing. In cases where preventive measures cannot totally overcome the influence of hereditary factors, parent education should focus on building self-esteem and address psychological issues.

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