Bottom Line: Obesity was associated with a shorter lifespan and an increased risk of illness and death from cardiovascular disease, and being overweight was associated with a lifespan similar to be being normal weight but a higher risk of developing cardiovascular disease younger.
Why The Research Is Interesting: In recent years, controversy has grown about the health implications of being overweight because of study findings on similar or lower death rates in overweight individuals compared with those of normal weight people. However, previous studies have not taken into account the age at onset of being overweight and the duration of cardiovascular disease (CVD).
Who and When: 190,672 in-person examinations of individuals without CVD at study entry, with follow-up from 1964 to 2015
What (Study Measures): Body mass index (BMI) categories (exposures); lifetime risk estimates of new CVD and different types of CVD, such as coronary heart disease and stroke, and years lived with and without CVD (outcomes).
How (Study Design): This was an observational study. Researchers were not intervening for purposes of the study and they cannot control natural differences that could explain study findings.
Authors: Sadiya S. Khan, M.D., M.S., Northwestern University Feinberg School of Medicine, Chicago, and coauthors
Results: Obesity was associated with shorter longevity and a greater proportion of life lived with CVD; being overweight was associate with a similar longevity to being normal weight but at the expense of a greater proportion of life lived with CVD.
Study Limitations: BMI at study entry was used without accounting for change in BMI across follow-up; BMI doesn't account for fat distribution in the body.