U.S. obesity rates have more than tripled over the last 40 years among those aged 19 and younger, according to Centers for Disease Control (CDC) data released Sept. 5.
Those 19 and younger saw the percentage of obesity rise from 5.2 percent to 18.5 percent, from 1971-74 data sets to 2015-16 data sets. Those considered severely obese rose from 1 percent to 5.6 percent.
The rate nearly tripled for those 20 and older, as well, increasing from 14.5 percent to 40 percent during this time period. Persons considered severely obese moved from 0.9 percent to 8 percent.
Obesity and severe obesity are designations based on a person’s body mass index (BMI), which is calculated using only a person’s height and weight.
For example, an adult who is 5 feet, 9 inches tall would be considered obese if they weighed 203 pounds or more. They would be severely obese at 271 pounds or more.
While BMI is considered an accurate tool for general assessment and evaluation, it should not be the sole measure for assessing obesity because factors like body type and muscle mass are not part of the calculation.
“BMI is a surrogate measure of body fatness because it is a measure of excess weight rather than excess body fat,” the CDC explains. “Factors such as age, sex, ethnicity and muscle mass can influence the relationship between BMI and body fat. Also, BMI does not distinguish between excess fat, muscle or bone mass, nor does it provide any indication of the distribution of fat among individuals.”
The obesity rate among women 20 and older increased from 16.6 percent in 1971-74 to 41.6 percent in 2015-16, while the rate among men 20 and older rose from 12.1 percent to 38.3 percent.
The rate for boys 19 and younger increased from 5.3 percent to 19.1 percent over the same time period, while girls 19 and younger rose from 5.1 percent to 17.8 percent.