Children's Hospital Colorado

Obesity in Children

What is pediatric obesity?

Pediatric obesity occurs when a child weighs significantly more than he or she should based on height and gender. It is a serious medical condition on its own, but is particularly important because of the other medical problems that can develop from it, called co-morbidities. These include type 2 diabetes, high cholesterol, high blood pressure, arthritis and obstructive sleep apnea.

What causes pediatric obesity?

Obesity is likely caused by many different factors in combination. Some people have a genetic pre-disposition to obesity, and being obese tends to run in families. Some children have hormone imbalances that can cause the condition.

However, for the most part, obesity is most strongly linked to eating too many calories and exercising too little. Many factors that are linked to these obesity factors are the result of changes in our society and culture over the last few decades including drinking more sweetened beverages, bigger portion sizes, more 'eating out' compared to cooking at home, not eating as a family, watching more television, playing more video games, exercising less and fewer physical education classes in school, to name a few.

Who gets pediatric obesity?

Children from both sexes and every race and ethnic background can develop obesity. The condition tends to run in families, so children of overweight parents may be more likely to become obese.

Experts estimate about 17% of children, or about 10 million kids in the United States are obese.

What are the signs and symptoms of pediatric obesity?

Unlike many other common childhood diseases, obesity may not be associated with physical problems or complaints until late in the illness. Although most of us feel that we can easily recognize an obese child or adult when we seen one, the reality is that from a medical standpoint a child has typically passed from being "overweight" to "obese" long before their parents recognize it.

For this reason we rely on regular tracking of a child's weight and height during well child exams from their primary care provider to tell us when a problem is developing. We typically use a measurement called the Body Mass Index (BMI) to assess a person's weight compared to their height to determine when there is a problem.

Like adults, the other physical complications of childhood obesity often go unrecognized until they are at advanced stages. Subtle indicators that a child's weight may be excessive and impacting their health may include:

  • Poor physical endurance or ability to keep up with friends
  • Shortness of breath with exertion
  • Snoring or long pauses in breathing while sleeping
  • Consistent complaints of pain in their knees, ankles or hips
  • Swelling or fluid accumulation in their lower legs or feet

In addition, increasing weight may cause worsening of known health issues such as asthma or gastroesophageal reflux/heartburn. Other worrisome signs or symptoms that may indicate medical problems caused by obesity include headaches, abdominal pain, daytime sleepiness, absent or irregular menstruation, persistently elevated blood pressures and depression.

What tests are used to diagnose obesity?

The most important test for obesity is the calculation of body mass index or BMI, using weight and height. To calculate BMI we take the child's weight in kilograms and divide it by their height in meters, squared. The BMI is usually a number between 10 and 40 in most children. In adults, cutoff values have been established to define "normal" (BMI between 18 and 25), "overweight" (25 to 30), "obese" (30 to 40) and "morbidly obese" (more than 40). In children, however, there are no cutoffs because the ranges change throughout childhood.

Typically BMI falls in the first few years of life until about age 4, and then rises until reaching the adult cutoffs at age 18. Therefore, someone with a BMI of 24 at age 10 would be considered "obese" though the same BMI for an adult would be within the normal range. As a result, we use percentiles to define the range of normal BMI in children. A BMI between the 5th and the 85th percentile for a given age is defined as "normal." A BMI between the 85th and 95th percentile is then considered "overweight" and above the 95th is considered "obese." Again, parents who consider their children as "thick" or "chunky" are often surprised when their BMI shows that they are above the 95th percentile and medically "obese."

There are some children, specifically those with a large amount of muscle mass, where the BMI may overestimate the amount of fat on their bodies, so the level must be taken into context. If an obesity problem is identified, your doctor may recommend screening your child for related conditions. This would typically include blood tests to check for elevated cholesterol or triglyceride levels, fatty liver disease and type 2 diabetes. In addition, your health care provider may perform additional screening for thyroid disease or kidney disease.

Sometimes, a doctor may suggest further testing if your child shows concerning signs or symptoms at the time of their visit. For example, if a child has had high blood pressure over a series of visits, further screening for cardiovascular or kidney disease may be considered with tests such as an echocardiogram or a kidney ultrasound. Other studies to look for rarer complications of obesity are sleep studies to check for sleep apnea and an MRI for double vision or neurological problems.

How is obesity treated?

Generally, treatment of pediatric obesity involves lifestyle and behavioral modification programs. The Weight Management Program at Children's Hospital Colorado can provide several options for treatment. 

Patients are not generally put on diets but rather receive education on proper nutrition and are encouraged to transition to a healthier diet. In some specific circumstances, specialized diets such as the protein-sparing modified fast (PSMF), low-fat and low calorie or other formal nutrition programs are used. At this time, there are no specific, FDA-approved, weight loss medications available for pediatric use, though medications are sometimes prescribed for specific medical issues related to obesity. In addition, weight loss surgery may be an option for patients with severe morbid obesity who have committed to a medical weight loss program for at least six months.

Otherwise, our program works to identify and treat any related medical problems, such as type 2 diabetes, fatty liver disease, hyperlipidemia, polycystic ovarian syndrome, gastroesophageal reflux disease, hypertension, pseudotumor cerebri, gallbladder disease, osteoarthritis, depression and others. For most of these, the best treatment is weight loss itself, but depending on the severity of illness additional treatment may be necessary.

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