Obese people live shorter lives and have a greater proportion of life with cardiovascular disease, a new study finds.
The study debunks the “obesity paradox,” a counterintuitive finding that showed people diagnosed with cardiovascular disease live longer if they are overweight or obese than people who are normal weight at the time of diagnosis.
“A healthy weight promotes healthy longevity or longer healthspan in addition to lifespan, so that greater years lived are also healthier years lived…”
The study shows similar longevity between normal weight and overweight people, but a higher risk for those who are overweight of developing cardiovascular disease during their lifespan and more years spent with cardiovascular disease.
This is the first study to provide a lifespan perspective on the risks of developing cardiovascular disease and dying after a diagnosis of cardiovascular disease for normal weight, overweight, and obese individuals.
“The obesity paradox caused a lot of confusion and potential damage because we know there are cardiovascular and non-cardiovascular risks associated with obesity,” says Sadiya Khan, an assistant professor of medicine at Northwestern University’s Feinberg School of Medicine and a cardiologist.
“I get a lot of patients who ask, ‘Why do I need to lose weight, if research says I’m going to live longer?”’ Khan says. “I tell them losing weight doesn’t just reduce the risk of developing heart disease, but other diseases like cancer. Our data show you will live longer and healthier at a normal weight.”
Obesity is defined as having a Body Mass Index of 30 to 39.9; overweight is 25 to 29.9. BMI is a person’s weight divided by his or her height. An overweight individual, who is 5’4″ and weighs 160 pounds, for example, would be considered overweight; a 5’4″ person who weights 190 pounds is considered obese.
Higher odds of a stroke, heart attack, heart failure, or dying from heart disease
According to the study:
- The likelihood of having a stroke, heart attack, heart failure, or cardiovascular death in overweight middle-aged men 40 to 59 years old was 21 percent higher than in normal weight men. The odds were 32 percent higher in overweight women than normal weight women.
- The likelihood of having a stroke, heart attack, heart failure, or cardiovascular death in obese middle-aged men 40 to 59 years old was 67 percent higher than in normal weight men. The odds were 85 percent higher in obese women than normal weight women.
- Normal weight middle-aged men also lived 1.9 years longer than obese men and six years longer than morbidly obese. Normal weight men had similar longevity to overweight men.
- Normal weight middle-aged women lived 1.4 years longer than overweight women, 3.4 years longer than obese women, and six years longer than morbidly obese women.
“A healthy weight promotes healthy longevity or longer healthspan in addition to lifespan, so that greater years lived are also healthier years lived,” Khan says. “It’s about having a much better quality of life.”
The study examined individual level data from 190,672 in-person examinations across 10 large prospective cohorts with an aggregate of 3.2 million years of follow-up. All of the participants were free of cardiovascular disease at baseline and had objectively measured height and weight to assess BMI. Over follow-up, researchers assessed for cardiovascular disease overall and by type, including coronary heart disease, stroke, heart failure and cardiovascular death, as well as non-cardiovascular death.
The researchers report their findings in JAMA Cardiology.
Funding for the study came from the National Institutes of Health/National Heart, Lung, and Blood Institute.
Source: Northwestern University