A piece of string may be more accurate in determining risky adipose tissue (body fat) levels than BMI (body mass index), which is a numeric calculation between the height and weight.
BMI has long been used as a tool in determining whether people are in the normal, underweight, overweight or obese category, but it fails to take into the account where in the body the fat is stored.
Research shows that additional fat storage is most harmful when stored as belly fat (around our organs), where it acts as a metabolically active, ‘additional’ organ.
According to research by Margaret Ashwell and Sigrid Gibson in Oxford University, a simple string test may be a better tool than BMI to see if one’s at risk of the negative implications of excess belly fat. Simply measure your height with a piece of string. Folding this sting in half, it should comfortably fit around your waist. If not, it would be beneficial for you to lose weight.
You can find the original study here