What are overweight and obesity?

Overweight is defined as the excess of body fat, more specifically a body mass index (BMI) , which is the ratio of weight to height above the 90th percentile for a child or teenager. Obesity is defined as a BMI above the 95th percentile for a child or teenager.

To calculate your body mass, use a BMI Calculator. But, don't focus on numbers. Dr. Jacalyn Hazen states, "Even though we can use specific measurements in defining ideal weight, we really focus on healthy lifestyle, including good nutrition and exercise, rather than just worrying about a 'number.'"

The American Obesity Association (AOA) estimates that 15 to 30 percent of children and teenagers are overweight or obese. This incidence has quadrupled in the past 25 years. Unfortunately, excess weight in childhood often leads to excess weight in adulthood.

What causes overweight and obesity?

Overweight and obesity are caused by:

  • Genetics: some people have a genetic tendency where they store fat and gain weight. Obesity is also more common in certain ethnic groups.
  • Behavior: some people do not understand how to lose weight or maintain a healthy weight 
  • Environment: some people live in an unhealthy environment where they do not have the opportunities to eat healthy foods. 

Society as a whole has a large impact on an increase in obesity in our culture. Whether it is the lack of exercise due to a focus on watching TV or playing video games, or due to an increase in consumption of food (especially fast food), something has changed in the culture to create this issue. 

Weight gain can occur over time. Dr. Gordon Blackburn says, "A 100 calorie excess each day accumulated over 1 year is a 10 pound weight gain, and a 200 calories excess each day consistently over 5 years is a 100 lb. weight gain!"

Here's the math:
100 calorie excess per day = 1 x 100 calorie snack bag and watching TV for 30 min/day (sedentary activity) instead of walking for 30 min/day = 10lb weight gain per year ! ! !

200 calorie excess per day = 1 x 15oz glass of orange juice per day and watching TV for 40 min/day (sedentary activity) instead of 40 min/day vigorous play = 100 lb weight gain over 5 years ! ! !

It's important to balance healthy foods with regular exercise to avoid weight gain.

Overweight and obesity: a social stigma

Unfortunately, the American society demands a certain body type if one wants to be accepted, and this body type is exactly the opposite of obese or overweight. Looking through magazines, and watching commercials on TV, it is all about being thin, which can cause serious psychological effects to those not fitting that bone-thin body type. 

Overweight children often experience weight-related teasing or name calling. Overweight teens may encounter unintentional comments or assumptions from peers or employers, who may assume that excess weight reflects laziness, inactivity or lack of self control

Girls in particular can develop poor self-esteem due to overweight. Girls in this category, can easily develop negative body image and try unhealthy ways to change their weight.

Health problems associated with obesity

Obesity can cause not only emotional but also physical problems. Common health problems associated with overweight and obesity include

  • Low energy
  • Adult onset diabetes, non-insulin dependent diabetes
  • High blood pressure
  • Sleep apnea , a potentially fatal condition involving pauses in breathing while sleeping
  • Fat accumulation in the liver, which can cause liver damage over time
  • Menstrual disorders
  • Heart disease

Preventing obesity

To prevent weight gain, one must concentrate on maintaining a healthy lifestyle, which consists of healthy eating habits, and exercise. 

Examples of healthy eating habits are: eating more fruits and vegetables, eating more whole grains, eating more low-fait dairy products, eating lean meats, eating less junk food and fast food, and drinking less soda.

It is also important to participate in regular physical activity. It may help to exercise with a friend – when someone is supportive, you’re more likely to reach your goals. Try to schedule your exercise on a daily calendar. It is helpful to have a hour set aside for activity only. Your exercise time is just as important as any other planned event.

For help with healthy nutrition, talk to your doctor or ask to speak to a registered dietitian specializing in teen or family health.


Reviewed: 12/13

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