Childhood Obesity

Obesity occurs when a child is significantly over the ideal weight for her height. Like adults, children become obese when they eat more calories than they use. Obesity in children is determined by using a body mass index (BMI) percentile. BMI is a measure of weight in relation to height.

Obesity can increase a child’s risk for serious and chronic medical problems, such as type 2 diabetes, high blood pressure (hypertension), high cholesterol, orthopedic problems, and liver disease.

Researchers continue to search for ways to treat obesity, but taking preventive measures has proven to be the best method so far. This means eating a healthy diet based on vegetables, fruits, legumes, whole grains, and lean protein. It is also important to maintain an active lifestyle by getting at least an hour of physical activity a day.

What are the causes of childhood obesity?

There are many reasons why a child may be obese, including medical or genetic ones. In most cases, though, children are overweight because they eat unhealthful foods and lead a sedentary lifestyle. If you think your child is overweight because of a medical condition, consult your pediatrician who can perform tests to check.

Reasons why more and more children are becoming obese include:

  • behavioral factors: eating bigger portions, eating foods that are calorie-rich but nutrient poor (junk foods), spending lots of time in front of the television or computer, and spending too little time doing physical activities
  • environmental factors: easy access to high-calorie junk foods, few opportunities for physical activity, lack of parks and playgrounds in some communities
  • genetic factors: A child is at increased risk for obesity when at least one parent is obese. However, genes do not necessarily mean a child is destined to be overweight — there are several steps a child can take to lower his risk.
  • medications: steroids, some antidepressants, and others
  • medical conditions: Genetic syndromes like Prader-Willi, and hormonal conditions like hypothyroidism are among the medical disorders that can cause obesity.

The “body weight set point theory” suggests that weight is determined by complex interactions of genetic, hormonal, and metabolic factors

How common is childhood obesity?

The Centers for Disease Control and Prevention estimate that 17 percent of 2- to 19-year-old American children are obese, as measured by their body mass index (BMI) percentile. The rate of childhood obesity has more than tripled in the past 30 years.

How is a child’s risk for obesity determined?

There are several tools your doctor might use to determine if your child is at risk for obesity, including:

  • plotting your child’s BMI percentile yearly to see if there's a sudden increase
  • identifying babies who gain weight too rapidly in infancy; studies show that these babies are at risk for becoming overweight as they get older
  • birth weight and gestational diabetes: these factors may increase a child’s risk for obesity and type 2 diabetes later in life
  • a family history of obesity, type 2 diabetes, hyperlipidemia, hypertension, sleep apnea, and early heart attack: these factors can also put a child at increased risk for obesity and associated medical complications

What are the symptoms of childhood obesity?

Each child may experience different symptoms but some of the most common include:

  • appearance: stretch marks on hips and abdomen; dark, velvety skin (known as acanthosis nigricans) around the neck and in other areas; fatty tissue deposition in breast area (an especially troublesome issue for boys)
  • psychological : teasing and abuse; poor self-esteem; eating disorders
  • pulmonary: shortness of breath when physically active; sleep apnea
  • gastroenterological : constipation, gastroesophageal reflux
  • reproductive: early puberty and irregular menstrual cycles in girls; delayed puberty in boys; genitals may appear disproportionately small in males
  • 骨科: flat feet; knock knees; dislocated hip

What are the long-term consequences of childhood obesity?

  • increased risk of being overweight or obese as an adult
  • increased risk for medical problems such as asthma, diabetes, heart disease, liver disease, reproductive problems, and some cancers
  • psychosocial disabilities, including social isolation, depression

How Boston Children’s Hospital approaches obesity

Boston Children’s has five hospital-based programs to help children and their families manage their weight.

  • Optimal Wellness for Life (OWL) Program: The largest pediatric weight management clinic in New England treats overweight children between 2 and 20.
  • The One Step Ahead program: Focused on prevention and management, OSA treats 3- to 13-year-olds who are part of the Boston Children’s Hospital Primary Care Center (CHPCC).
  • STEP: Based in the Adolescent and Young Adult Clinic at Boston Children’s, this multidisciplinary program works with 13- to 25-year-olds in their primary care clinic to develop a teen- and young adult-friendly approach to weight and lifestyle management.
  • Preventive Cardiology Clinic (Lipid Clinic): The preventive cardiology program serves patients who have elevated lipid levels and/or hypertension. Seventy percent of the children seen in this program are obese, and thus many of the interventions focus on the same types of lifestyle and behavior changes as the clinical obesity programs.
  • Adolescent Bariatric Surgery Program: This multi-disciplinary program for adolescents who are considering surgical interventions to reduce weight. Patients must have attempted at least six months of medically supervised weight loss before they would be considered for eventual surgery.