Beyond BMI: New Obesity Measure May Better Predict Death
For decades, researchers and health practitioners have used the Body Mass Index (BMI) as a simple metric for obesity and indicator of health risks, including increased risk of cancer. Now researchers have developed a new index to measure obesity that may provide a better correlation with death rate, independent of BMI, according to a study released last week. The new index, A Body Shape Index (ABSI), was published in open access journal PLoS ONE,
The BMI uses a person’s height and weight to calculate a number that falls into a category, such as healthy weight, overweight, or obese. The index has recognized flaws, a healthy BMI for Asians is different than that for Blacks, for example. The BMI categories may also not apply to athletes and the elderly. And over the years, research has shown that excess abdominal fat is an independent risk factor for increased cancer risk as well as other diseases.
The ABSI uses both BMI and waist circumference in its calculations.
To study the new measure, the authors analyzed data from over 14,000 US adults taken as part of the National Health and Nutrition Examination Survey. After looking at mortality data over a five-year period, they found that ABSI was a better predictor of premature death compared to BMI or waist circumference, independently. The correlation held across the range of ages, for both sexes, and for both black and white ethnicities. It did not apply to people of Mexican ethnicity.
ABSI could complement the other measures and risk factors, conclude the authors. But further longer-term studies are needed to connect ABSI to both premature mortality and quality of life.
Source: Krakauer NY, Krakauer JC. A New Body Shape Index Predicts Mortality Hazard Independently of Body Mass Index. PLoS ONE, 2012; 7(7): e39504 DOI: 10.1371/journal.pone.0039504