The rise in prevalence of childhood obesity in the United States over the last four decades is very concerning. According to the U.S. Department of Health and Human Services, 16 percent of children between the ages of 6 and 19 were overweight in that time period. Parents and pediatricians should take measures to track their child’s weight and height over time; this information can be used to calculate the BMI, or body mass index. The BMI is the most important tool to diagnose obesity. Evidence suggests that early interventions can prevent many of the complications of obesity later in life. Body Mass Index BMI is used by clinicians to get a rough idea of a person’s nutritional status. The formula for BMI factors in an individual’s height and weight. Normal values in the adult population are approximately 18.5 to 24.9; values between 25 and 29.9 are considered overweight and those between 30 and 34.9 are considered obese. A BMI over 40 is classified as morbidly obese.
BMI in children are different from adults because they are in an active state of growth and undergo a variety of changes during this time. The amount of fat stores in children changes over time as they grow. Instead of using BMI to assess for obesity, pediatricians use a variation of this formula by taking the BMI for age. A child’s BMI is compared to the reference range for his age. For example, the 95th percentile of BMI in a 4-year-old is 19, whereas it is 25 in a 13-year-old.
Diagnosing Obesity BMI percentiles from 5 to 84 for age are considered normal weight. Values from 85 to 94 for age are classified as “at risk for overweight” and those over the 95th percentile for age are classified as obese. However, BMI measurements can overestimate weight in muscular children. Doctors can track a child’s change in BMI over years by using convenient charts provided by the Centers for Disease Control. Separate charts are available for boys and girls. Other tools that can be used to assess for nutritional status are skinfold thickness, ultrasound, total body conductivity and air-displacement plethysmography, which is a technology that uses air to measure body fat . While BMI has many disadvantages, it is most commonly used by doctors as it can be measured inexpensively and reliably.
The importance of tracking a child’s BMI lies in the fact that obesity is associated with a number of complications. Besides social stigmatization which can be damaging to a child’s self-esteem, childhood obesity is associated with an increased risk of hypertension, high cholesterol, diabetes and heart disease later in life. Behavioral changes such as limiting screen time and increasing physical activity have shown promise in preventing many of these complications. Dr. Priti Kothari, a child psychiatrist in Boca Raton Florida has a special interest in the rising statistics of obesity in children and teens. She is also the medical director for Dr Kahlil Shillingford’s weight loss surgery practice which encompasses procedures of lap band, gastric sleeve and gastric bypass surgeries.
