Obesity

What is obesity?
Obesity is defined as a generalized accumulation of body fat. Obesity is determined by measuring both the height and weight of the adolescent. An adolescent is considered obese if he/she is significantly over the ideal weight for his/her height. Overweight is defined as increased body size with increased lean body mass and without excess accumulation of body fat. A uniform standard to separate obesity from overweight has not been established. Research studies suggest that overweight adolescents may become overweight adults.


What causes obesity?
During the 1990s, one physiologist proposed a "set point theory" which has continued to gain support. The set point theory suggests that weight is determined by complex interactions of neural, hormonal, and metabolic factors. Genetic and familial influences contribute to metabolic rates and physical activity levels important to energy expenditure. Some effort is now being made to address two types of obesity:

  1. Obesity with specific organic etiology (endogenous).
  2. Obesity caused by simple excessive caloric intake, genetic/familial, psychogenic and mixed factors (exogenous).
  3. Adipocytes (fat cells) appear to increase in number when caloric intake is increased beginning before birth and continuing at a reduced rate through puberty. During adolescence, when periods of weight reduction normally occur, the size of adipocytes decrease, but the number of cells does not decrease.

Who is affected by obesity?
Physical factors contributing to excess body fat in adolescents include the following:

  • Increased insulin levels.
  • Elevated lipid and lipoprotein levels.
  • Elevated blood pressure.

Behavioral and other factors contributing to a positive energy balance stored as fat over long periods of time include the following:

  • Excessive intake of high energy foods.
  • Inadequate exercise in relation to age.
  • More sedentary lifestyle.
  • Low metabolic rate.
  • Increased insulin sensitivity.

What are the symptoms of obesity?
The following are the most common symptoms that indicate an adolescent is obese. However, each adolescent may experience symptoms differently. Symptoms may include:

  • Facial features often appear disproportionate.
  • Adiposity (fat cells) in the breast region in boys.
  • Large abdomen (white or purple marks are sometimes present).
  • In males, external genitals may appear disproportionately small.
  • Puberty may occur early.
  • Increased adiposity in the upper arms and thighs.
  • Genu valgum (knock-kneed) is common.

Adolescents who are obese often experience significant social pressure, stress, and difficulties accomplishing developmental tasks. Psychologic disturbances are also very common. The symptoms of obesity may resemble other conditions or medical problems. Always consult your adolescent's physician for a diagnosis.

How is obesity diagnosed?
Obesity is diagnosed by a physician. The body mass index (BMI) is usually used to define obesity in adolescents. Two categories are defined, including the following:

  • BMIs at the 95th percentile or more for age and sex or BMIs of more than 30 (whichever is smaller).

  • BMI findings in this category indicate the need for a complete medical work-up.

BMIs between the 85th and 95th percentile or BMIs equal to 30 (whichever is smaller) suggest a second level screening which includes evaluation of five areas of health risks including the following:

  • Family history of cardiovascular disease, parental elevated total cholesterol, diabetes, parental obesity.
  • Elevated blood pressure.
  • Total cholesterol level.
  • Large increases in BMI assessments from year to year.
  • Concerns about weight, including personal (emotional or psychological).
  • Concerns related to weight and perception of self as overweight.

Treatment for obesity:
Specific treatment for obesity will be determined by your adolescent's physician based on:

  • Your adolescent's age, overall health, and medical history.
  • Extent of your adolescent's symptoms.
  • Your adolescent's tolerance for specific medications, procedures, or therapies.
  • Expectations for the course of the condition.
  • Your opinion or preference.

Treatment for obesity in adolescents may include the following:

  • Nutritional and individual diet counseling.
  • Modification of diet and caloric content.
  • Increased exercise or participation in an appropriate exercise program.
  • Behavior modification.
  • Individual or group therapy focused on changing behaviors and confronting feelings related to weight and normal developmental issues.
  • Support and encouragement for making changes and following recommended treatment recommendations.

Treatment planning to address the above components often include the involvement of a nutritionist, qualified mental health professionals, and an exercise specialist. Treatment goals should be realistic, focused on modest reduction of intake, changes in eating habits, and the incorporation of a healthy exercise-oriented lifestyle.

Prevention of obesity:
Preventive measures to reduce the incidence of obesity are not known at this time. Encouraging healthy eating habits and realistic attitudes toward weight and diet are important. Early detection and intervention into unhealthy eating and lifestyle habits can impact weight related issues, enhance the adolescent's normal growth and development and improve the quality of life experienced by adolescents with a physical predisposition or behavioral tendencies toward obesity.

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