Over 450 pounds. That's what a 14-year-old boy who came in for his first appointment with me weighed. Our office scale only goes up to 450 pounds, so we were unable to get his exact weight. We were unable to get a blood pressure because our extra-large adult blood pressure cuff was too small for him. Although he had no specific complaints that day, an abnormal amount of glucose (sugar) was found in his urine. Subsequent blood work showed high insulin and high hemoglobin A1C levels — signs of early type 2 diabetes.

With extreme obesity comes an extremely high risk of diabetes. Extreme obesity is a body mass index at or above the 120th percentile. BMI is calculated with the body weight (in kilograms) divided by the height (in meters) squared. It is interpreted differently for children and teens than it is for adults even though it is calculated as weight ÷ height2. Because children and teens have changes in weight, height, percent body fat and percent lean body mass with age, BMI levels need to be expressed relative to other children of the same sex and age. On this basis, the Centers for Disease Control and Prevention defines the levels of overweight, obesity and extreme obesity in children and teens:

  • Overweight: BMI at or above the 85th percentile
  • Obese: BMI at or above the 95th percentile
  • Extreme obesity: BMI at or above the 120th percentile

Obesity, especially extreme obesity, has become a growing problem among adolescents. A study recently published in the Journal of the American Medical Association found these disturbing trends between 1988 and 2014 for 12- to 19-year olds:

  • Obesity doubled from 10.5 percent to 20.6 percent.
  • Extreme obesity more than tripled from 2.6 percent to 9.1 percent.

A 17-year-old girl at her first visit with me weighed 322 pounds. She was found to have high liver enzymes. An abdominal ultrasound showed nonalcoholic fatty liver disease, yet another serious complication of extreme obesity.

Nonalcoholic fatty liver disease is a term used to describe the accumulation of fat in the liver of people who drink little or no alcohol. Nonalcoholic fatty liver disease can progress to liver failure. Other chronic medical complications that can start in the teenage years include high blood pressure, high cholesterol, liver disease, and, for girls, younger onset of menstrual periods and menstrual irregularities.

A 275-pound 15-year-old boy was home-schooled because is classmates were bullying him about being obese and he refused to go to school. Unfortunately, he continued to gain weight during the six months after starting online school.

Teasing and bullying of overweight teenagers is common. Compared with teens of average weight, overweight, obese and extremely obese adolescents are at greater risk of psychosocial problems including low self-esteem, poor social skills, anxiety, depression and suicidal thoughts.

Most extremely obese teens remain extremely obese as adults. As a result, they may have a shorter life expectancy than normal, according to data pooled from 20 large studies of people from three countries. As their BMI increases, so does their risk of dying early due to heart disease, cancer and diabetes. They may lose from 6.5 years (BMI of 40-44.9) to 13.7 years (BMI of 55-59.9) of life.

What can parents do to counteract these disturbing trends? Here's my advice:

1. Don't buy sugar-sweetened beverages. Today, Americans consume four times the amount of sugary drinks than they drank in 1965. Sugar-sweetened beverages supplied an average of 270 kcal/day — 10-15 percent of their total calories, according to surveys of children in the United States. Studies have found strong evidence that these drinks are a major contributor to obesity and diabetes.

2. Turn off the television. Research has shown that the amount of time a teen spends watching TV is directly related to obesity in children and adolescents. That's because television watching replaces physical activity and decreases metabolic rate, making weight gain likely.

3. Encourage exercise every day. This requires an attitude and lifestyle change. The new attitude should be to exercise to be fit. Strong is the new skinny!

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