Waist to height ratio is much easier to calculate than BMI — and easier to track changes.
A Better Way to Assess Body Fat and Health Risk?
"Keeping your waist circumference to less than half your height can help increase life expectancy for every person in the world," says researcher Margaret Ashwell, PhD, of Ashwell Associates, in Hertfordshire, England.
Calling waist-to-height ratio a "one-size-fits-all approach," Ashwell says that it should replace BMI and waist circumference alone as a way to assess body fat and health risks everywhere.