One in two American adults will have obesity within 10 years, and one in four will have severe obesity, which typically means carrying around more than 100 pounds of excess weight, according to a study published in the New England Journal of Medicine (NEJM).

The study also estimates that no state, including Minnesota, will have an adult obesity rate of less than 35 percent by 2030, and more than half of the states — 29 — will have a rate greater than 50 percent.

Just seven years ago, no state had an adult obesity rate above 35 percent.

Currently, 40 percent of American adults have obesity (defined as a body mass index, or BMI, of 30 to 34.9), and 18 percent have severe obesity (a BMI of 35 or higher), the study’s authors estimate.

A report published earlier this year put Minnesota’s adult obesity rate at 30.1 percent. The NEJM study predicts the state’s rate will jump to 46.1 by 2030. It also predicts that the state’s severe obesity rate will reach 20.4 percent.

These grim predictions have major health and economic implications. As I’ve noted in Second Opinion before, people with obesity, especially severe obesity, are at increased risk for many health problems, including high blood pressure, coronary heart disease, stroke, type 2 diabetes, certain cancers (including breast, colon and kidney), osteoarthritis and clinical depression.

Obesity is estimated to cost the U.S. economy at least $149 billion each year in increased medical expenses — half of which is paid for by Medicare and Medicaid. Minnesota’s obesity-related health care costs are estimated at $3.2 billion annually.

More realistic data

To make their projections, the authors of the NEJM study — a team of researchers from Harvard University and George Washington University — analyzed more than 20 years of BMI data on 6.2 million American adults. The data had been collected through national telephone surveys conducted regularly by the Centers for Disease Control and Prevention (CDC).

Because people tend to under-report their weight, the Harvard and George Washington researchers adjusted the CDC data to better align with a smaller national study in which BMI was determined more objectively by measuring people’s height and weight during standard medical exams. (BMI is calculated by dividing a person’s weight by height.)

The researchers then used that adjusted data to make their obesity predictions — specifically, that 48.9 percent of American adults will have obesity and 24.2 percent will have severe obesity by 2030.

They also took take a deeper dive into the large database to determine obesity rates for individual states and specific demographic groups.

An alarming trend

On all those levels, the study’s findings are alarming, particularly the speed at which Americans are putting on excess pounds.

“Severe obesity has typically been a rare condition. But we find that it’s growing pretty rapidly in a lot of states,” says Zachary Ward, the study’s lead author and a programmer/analyst at Harvard University’s Center for Health Decision Science, in a video released with the study.

Indeed, some states, most notably Alabama, Arkansas, Mississippi, Oklahoma and West Virginia, will likely have obesity rates nearing 60 percent in 10 years, the study predicts.

Ward and his colleagues also predict that by 2030 severe obesity will be the most common BMI category nationally among women, black adults and those with an annual household income of less than $50,000.

And that will be true across the country.

“We find that for very low-income adults — adults with less than $20,000 annual household income — severe obesity will be the most common BMI category in 44 states — basically, everywhere in the country,” Ward says.

More effort on prevention

It may be possible to slow down the trends predicted in the study, but it’s going to take concerted and aggressive action.

“There’s a lot that state policymakers can do, actually,” says Ward. “One of the most effective interventions — cost-effective interventions — that we found is limiting intake of sugar-sweetened beverages.”

Previous research, he points out, has found that taxing sugar-sweetened beverages is particularly effective at reducing the consumption of such products. And the cost to governments of implementing a beverage tax is more than likely to be offset by the savings in health care related expenses, he adds.

“In much of our work we find that prevention really is going to be the key to better managing this epidemic,” Ward stresses. “It’s really hard to lose weight. It’s really hard to treat obesity. And, so, prevention really has to be at the forefront of efforts to combat this epidemic.”

FMI: You’ll find an abstract of the study on the NEJM website, but the full study is behind a paywall.