By Susan Heavey
WASHINGTON (Reuters) - Here's one more reason to dread aging: older Americans are seeing a greater increase in obesity rates, according to a survey released on Wednesday.
Data from nearly 600,000 U.S. adults showed that people aged 18 and older were more likely to be obese than they were in 2008, according to the Gallup survey. Researchers noted a significant jump among adults in their 40s, 70s and 80s.
"Middle-aged adults and advanced seniors were the most likely to see an increase in the percentage of people in that age group with higher obesity rates than four years ago," the national polling firm said.
"Most Americans who are over the age of 35 are now significantly more likely to be obese than those who were that same age four years ago," it added.
Gallup interviewed 579,210 U.S. adults in 2008 and again between January 1 and September 30, using respondents' self-reported height and weight to calculate their body mass index, or BMI.
BMI, though sometimes criticized as a measure, is widely used to determine whether someone has a healthy weight. Scores of 30 or higher are considered obese, while those between 25 and 29 are "overweight." A BMI of between 18.5 and 24 are deemed "normal."
For example, a 5-foot, 6-inch woman who weighs 186 pounds or more would qualify as obese. A man who is 6-feet tall and weighs 221 pounds would also be considered obese.
U.S. obesity rates have been climbing for years, and about two-thirds of Americans are already too heavy.
But while federal and local authorities have waged very public campaigns to tackle childhood obesity, Gallup's findings shed light on the issue for older Americans.
Extra pounds can increase the risk of serious diseases such as diabetes and chronic heart disease, contributing to soaring U.S. healthcare costs.
The Gallup-Healthways Well-Being Index found that people aged 40 to 43 saw a nearly 2 percentage point increase in obesity rates between 2008 and 2012, while those aged 44 to 47 saw a 2.5 point rise.
Seniors also saw a jump, with those ages 72 to 79 and 84 to 87 seeing about a 2 point increase, according to the survey, which has a margin of error rate of plus or minus 1 percentage point.
"The increase in obesity among middle-aged adults is particularly troubling, because it means these adults will face the health risks of maintaining an unhealthy weight for a longer period of time, resulting in a lower quality of life, more health problems, and a shorter lifespan," Gallup experts wrote.
It's also a worry for seniors, who may not have as long to live, but could see a serious impact on their overall well-being and quality of life, they said.
"More effort should be put into helping seniors stay active and informed about their nutritional needs," they wrote.
One bright spot in the findings is the smaller increase in obesity rates among 18- to 27-year-olds who saw little (half a percentage point) or no increase.
"The minimal increase in obesity rates among the youngest age groups ... is promising, because it may indicate that efforts to improve nutritional awareness and foster more exercise among the nation's youth may be working," they said.
But it could be bad news, too, they added: "It could mean that obesity has reached a saturation point among the young."
(Reporting By Susan Heavey; Editing by Stacey Joyce)