WEDNESDAY, March 24, 2021 (HealthDay News) -- For people who are obese, even a small amount of weight gain may come with higher medical costs, a new study finds.
It's well known that obesity contributes to health conditions like arthritis, diabetes, heart disease and certain cancers -- and health care costs reflect that.
But the new study dug a little deeper into the connection between weight and medical costs. Overall, health care costs for obese adults were nearly $1,900 higher each year, compared to their normal-weight peers. And once adults were in the "obese" category, even incremental increases in weight meant additional health care expenses, the researchers found.
The findings, based on nearly 180,000 Americans, sound like bad news.
Viewed a different way, though, they also suggest that small improvements in weight could save health care dollars.
"You could see this as glass half-full, half-empty," said Marlene Schwartz, director of the Rudd Center for Food Policy and Obesity at the University of Connecticut.
"On one hand, it's not just categorical shifts in BMI that increase health care costs -- it's small shifts, too," said Schwartz, who was not involved in the study.
"On the other hand," she added, "that suggests even small improvements in BMI could make a difference."
BMI, or body mass index, is a measure of weight in relation to height. It's often described in terms of categories: A BMI of 30 to 34.9 is the "obesity class I" category, 35 to 39.9 is "class II," and a BMI of 40 or higher is "class III" or "severe" obesity.
In this study, once people reached a BMI of 30, even a one-unit increase caused annual health care expenses to creep up -- by an extra $253 per person.
Not surprisingly, severe obesity carried the heftiest price tag -- costing an additional $3,100 per person, versus Americans with a normal BMI.
Still, study leader Zachary Ward agreed that the findings can be seen in a positive light.
Even if obese adults cannot lose a substantial amount of weight -- a difficult feat, Ward noted -- there could be benefits from modest weight loss, or even from preventing further weight gain.
"If people can maintain their current weight as they age, that might avert some of these extra health care costs," said Ward, a research scientist at the Harvard School of Public Health.
The study, published March 24 in the journal PLOS ONE, comes at a time of soaring obesity rates among Americans. As of 2018, more than 42% of U.S. adults were obese, according to the U.S. Centers for Disease Control and Prevention. That was up from 30% about 20 years ago.
Just over 9% of adults are severely obese, the agency says.
The latest findings are based on more than 175,000 adults and children who took part in one of two federal health surveys.
Overall, Ward's team calculates, adulthood obesity accounted for nearly $173 billion in annual medical expenses nationally.
In general, obesity-related health care costs were greatest for people in their 60s, Ward said. But, he added, obesity in kids and young adults is a concern, in part, because they are likely to be obese as they grow older.
Ward said childhood is an ideal time for prevention -- both because the earlier, the better, and because it's generally easier for programs to reach children.
Schwartz agreed. "It's so important to focus on good nutrition in childhood," she said. "And it's an area that government can regulate."
Schwartz pointed to efforts to make fresh produce and other healthy foods more accessible to low-income Americans, through the Food Stamp and Women, Infants and Children programs. The National School Lunch Program also has updated its nutrition standards to boost kids' fruit and vegetable intake.
But it's also never too late for adults to make diet changes or start exercising. It is an uphill battle, Schwartz noted, and as people age, they are fighting the natural slowdown in metabolism.
As the latest findings suggest, though, even preventing further weight gain -- particularly the slide into severe obesity -- can be considered a win.
"Every step in the right direction counts," Schwartz said.
But for individuals to succeed, she noted, they need help. When healthy choices are made easier -- a workplace with fruits and vegetables rather than vending machines full of junk food, for example -- people will respond, Schwartz said.
The U.S. Department of Agriculture has advice on low-cost healthy eating.
SOURCES: Zachary Ward, PhD, MPH, research scientist, Center for Health Decision Science, Harvard T.H. Chan School of Public Health, Boston; Marlene Schwartz, PhD, director, Rudd Center for Food Policy and Obesity, and professor, human development and family sciences, University of Connecticut, Hartford; PLOS ONE, March 24, 2021, online