CDC report finds more than 40% of U.S. adults are obese

More than 40% of American adults are obese, a significant increase since the start of this century, and nearly 10% are severely so, federal health researchers said Thursday.

Obesity rates have climbed 12 percentage points from 1999-2000 to 2017-2018, increasing from 30.5% to 42.4%, according to a new report released by the Centers for Disease Control and Prevention. The percentage of Americans who are severely obese nearly doubled in the same time frame, from 4.7% to 9.2%.

“Those are really the highest numbers we’ve ever reported for obesity and severe obesity in the U.S. population,” said Cynthia Ogden, one of the report’s authors and an epidemiologist at the CDC’s National Center for Health Statistics. “Prevalence is increasing and there are certain health risks, especially for severe obesity.”

The study includes the measured weights and heights of more than 5,000 adults aged 20 years and older. Forty percent of younger adults aged 20 to 39, 44.8% of middle-aged adults aged 40 to 59, and 42.8% of older adults aged 60 and older were obese. Women were more likely to be severely obese than men, at 11.5% compared to 6.9%.

Obesity prevalence was highest among non-Hispanic black adults at 49.6% and the lowest among non-Hispanic Asian adults at 17.4%. Hispanic and non-Hispanic white adults ranked in the middle at 44.8% and 42.2% respectively.

The upward tick in obesity in the U.S. is a trend that Dr. Rekha Kumar described as “really concerning.”

“We will see a significant increase in type 2 diabetes, heart disease, liver complications. There will be a lot of mobility issues because of arthritis and stress on joints. We’ll definitely start seeing more of an economic burden due to people missing more work due to these complications. Medical bills will be higher for every individual experiencing obesity,” said Dr. Kumar, the medical director of the American Board of Obesity Medicine.

“Despite whatever interventions we’ve taken in the medical community and in the public health world, we need to be more aggressive,” she said.

There were slight increases in both obesity and severe obesity rates from 2015-2016, the last time the CDC gathered data, but the study authors note the differences are not statistically significant.

Just under 40% of adults were obese in 2015-2016 and about 8% were severely obese, the CDC reported.

Compared to the early 1960s, when the severe obesity rates hovered around 1%, the severe obesity rates have increased tenfold, Dr. Ogden pointed out.

The increase in obesity correlates with the transformation of the global food supply in the 1970s, Dr. Kumar said, noting bigger portions and the availability of more fast foods, processed foods and refined carbohydrates.

“There was a change in the food supply plus there was also a change in the amount of energy expended at home and at work,” she said. “With more technology incorporated in our lives, people burn less calories at work. I also think people are sleeping less than they did 30 or 40 years ago, and sleep deprivation can contribute to metabolic problems and weight gain.”

To address this public health issue, Dr. Kumar said all physicians and health care providers should be aware of obesity interventions such as diet and exercise, FDA approved medications for weight control and bariatric surgery.

She also recommended that those who fall under a normal weight seek dietary and exercise advice from an expert to avoid gaining weight.

Obesity in adults is defined as a body mass index of 30 or more, while severe obesity is defined as a BMI of 40 or more.