Why many BMI studies are flawed

Researchers have been confusing correlation with causation

Several recent studies have underestimated the harmful effects of being overweight, according to researchers who analysed mortality data for 60,000 parents and their children.


The researchers say it is incorrect to assume that being overweight might be the healthiest weight range in terms of BMI because it appears to be associated with longevity.

They say the pro-overweight conclusion is flawed because correlation has consistently been confused with causation.

"We found that previous studies have underestimated the impact of being overweight on mortality and