Mathematicians, tall ones presumably, have found that the formula used to calculate body mass index (BMI) has made tall people more overweight and short people not fat enough.
Apparently the current system does not take into account that a person’s weight grows with their height, giving taller people more room to bulge.
Prof Nick Trefethen, a leading mathematician, has devised a new formula.
“The NHS relies on the BMI pervasively in all of its public discussions of obesity,” he told The Telegraph.
“We deserve an explanation of what justification they have for using this formula.
“BMI divides the weight by too large a number for short people and too small a number for tall people.”
“So short people are misled into thinking that they are thinner than they are, and tall people are misled into thinking they are fatter.”
The BMI formula, used by doctors to find out if people are overweight is calculated by dividing a person's weight in kilograms by their height in metres squared.
But this assumes people scale up according to a model of growth, in which they get taller more quickly than they bulk out.
The new formula would add a whole BMI point, enough to push people who are five foot tall and on the cusp of "normal" weight into the "overweight" category. Other vertically challenged people will find themselves in the 'obese' category.
Via: The Telegraph
