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Middle-Age Spread Can Shave 5 Years Off Your Life

Researchers found a strong association between BMI and longevity

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sefa ozel / Getty Images


Need another reason to lose weight? A new study led by researchers at Northwestern University found that people who were obese in middle age died nearly five years earlier than those who weren’t. What’s more, individuals who are overweight in middle age had more health issues than their thinner counterparts. 

In 2014 the longevity rate in America fell for the first time in over two decades. Much of the blame was placed on an increase in cardiovascular disease despite a bevy of research papers that showed obesity had a negative impact on overall health and a person’s life span. To see if there is a direct link between body mass index (BMI) and longevity, researchers analyzed medical insurance data for 29,621 people age 65 and older who participated in a health survey in the 1960s and 1970s. Of those survey participants, by December of 2015, 13,000 had passed away. It was that group the researchers studied to find a link between BMI, obesity and health care costs.

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BMI and longevity

In order to analyze the death rates, researchers put the deceased study participants into groups based on BMI. BMI measures body fat based on height and weight. The U.S. Department of Health and Human Services breaks it down as follows: ​

  • BMI of less than 18.5 = underweight​​
  • BMI between 18.5 and 24.9 = normal weight​​
  • BMI of 25 to 29.9 = overweight​​
  • BMI of 30 or more = obese​​

Researchers also looked at the longevity rates of the subjects and health care costs across the different BMIs. After pouring over the data, the scientists found that people with higher BMIs had shorter life expectancy rates and spent more years in poor health. That, in turn, translated into more money for health care. 

Those who fit into the obese category, with BMIs of more than 30, lived, on average, to 77.7 years old. Those who were in the 25 to 29.9 range lived to 80.8. The difference between people who landed in the normal and slightly overweight categories was slim, with both living to around 82 years. The slightly overweight people did have 7.22 years, on average, of poor health and spent $12,390 more on health care costs than their thinner counterparts, who lived 6.10 years in poor health. Severely obese people lived 10.2 years in poor health, spending $23,396 more for health care than those individuals who were a normal weight.

“Our findings provide evidence that overweight or obesity status decades earlier, in midlife, is independently associated with a greater cumulative burden of morbidity in older adulthood,” wrote the researchers in a report published in the journal JAMA Network Open. “This association also translated to higher health care costs in older adulthood. Resources and strategies are urgently needed at the individual and population level to address the growing public health challenge of excess weight in the context of an aging population.”​

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