The ‘obesity paradox’—which suggests that people who are overweight have greater protection against serious heart problems—has finally been put to rest.
The paradox comes about because the BMI (body mass index) score—routinely used to assess obesity—is inexact and misses key features such as the time someone has been obese and muscle mass.
A better predictor of heart disease is by measuring waist measurement against height, say researchers from the University of Glasgow.
Using this ratio—or simply waist circumference or waist-to-hip measurements—were all more accurate ways of predicting heart disease and survival.
The researchers took a fresh look at data from 1832 women and 6567 men who had suffered heart failure, and whose BMI and waist and body measurements had been recorded by doctors at the time.
Just looking at the BMI measure, people with scores that were 25 kg/m2 or above—defined as overweight and a score greater than 30 is classified as obese—seemed to survive their heart attacks. But this obesity paradox disappeared when other measures were instead applied. Using the waist-to-height ratio, the researchers saw that the risk of death and hospitalisation increased with the amount of body fat the patient had.
People with the most body fat had a 39 percent increased risk of needing hospital care for heart failure compared to those with the least amount of body fat.
“We knew the obesity paradox could not be correct and that obesity must be bad rather than good,” said John McMurray, one of the researchers.
