The Body Mass Index (BMI) is the most widely used system by doctors to gauge whether or not a person is healthy, overweight or obese.
A new study by Loughborough University and the University of Sydney, the largest of its kind, suggests that waist to hip ratio is a better indicator of the potential health risks associated with excess weight.
Over ten years, the study, published in the Annals of Internal Medicine, observed the BMIs and waist measurements of 42,702 men and women in the UK, and looked to see if there was an increased risk of death for people carrying extra weight around their middle (central obesity) compared to those carrying it elsewhere.
Those who had a normal BMI (between 18 and 25) but also ‘central obesity', thus a high waist to hip ratio, had a 22% increased risk of death. Obese participants (BMI 30+) with central obesity also had increased risk. Surprisingly, overweight individuals (BMI 26-30) with central obesity did not have increased risk. The researchers aren't sure why this is, but claim there is a link between extra fat stored around legs and hips and a healthier metabolism.
What is an unhealthy waist to hip ratio?
If a person has a waist to hip ratio of 0.85 or more for women, and 0.9 or more for men, this indicates high levels of visceral fat, which is linked to cardiovascular disease, diabetes and stroke. Anything below these values is deemed healthy.
Should I ignore BMI altogether?
According to studies from the Archives of Internal Medicine and Epidemiologic Reviews, BMI measurements can be useful in predicting risk of diabetes and stroke. However, BMI calculations can give inaccurate results as they don't take lean muscle mass into account - professional athletes carrying extra muscle may fall into ‘overweight' or ‘obese' categories despite being extremely healthy overall. In addition, a study published in The American Journal of Clinical Nutrition in 2006 stated that waist to hip ratio is a better predictor of mortality, especially for people over the age of 75.
How do I find my waist to hip ratio?
Measure your waist at the narrowest point between your ribs and hips after exhaling, make sure the measure is snug but not pinching. Then take a measurement at the widest part of your hips and enter into Health Status' calculator
