Since the 19th century, body mass index (BMI) has been heralded as the pillar of the medical community's basis for determining the relationship between body size and health status. However, emerging research, particularly that of two scientists in New York, is suggesting that there is a better way to predict the likelihood of dying prematurely based on your body shape. This new calculation focuses more on body shape rather than simply calculating weight in proportion to height.

The New Measurement Tool

The two scientists proposing this new measurement tool, dubbed "A Body Shape Index," are father and son team, endocrinologist Dr. Jesse Krakauer and assistant engineering professor Nir Krakauer. The Body Shape Index, abbreviated ABSI, adds a third component to the current BMI calculation. BMI is calculated by using just an individual's height and weight. ABSI is calculated using a person's height, weight and waist circumference. The scientists behind this new measurement tool believe combining BMI with waist circumference more accurately predicts if someone has a "hazardous body shape."

The researchers say this new equation will better forecast how an individual's body shape and amount of body fat will negatively affect his or her health. The reason this new calculation could be more accurate at determining tendency towards illness or early death is because it accounts for abdominal fat. Central adiposity, where fat is deposited in and around your internal organs, is much more dangerous than fat deposited elsewhere on your body, such as your hips or thighs.

How Accurate Is BMI?

While BMI is a valid tool for measuring likelihood of illness or premature death in a large group of people, it has its limitations when used on individuals. There are certain people for which the BMI calculation would provide inaccurate results, such as athletes or those with a high proportion of lean muscle mass compared to fat mass, but whose weight may technically and incorrectly put them in the overweight or obese category.

It's not surprising that these researchers thought to look more closely at waist circumference when trying to determine one's risk for illness or premature death, because waist circumference is a strong indicator of health status. A waist circumference of 35 inches or higher on a woman and 40 inches or higher on a man, coupled with a BMI of greater than 24.9, significantly increases the risk of heart disease, diabetes, high blood pressure, high cholesterol, and certain cancers.

The Bottom Line

While the researchers believe ABSI is reliable, they do say that further research needs to be done before it should be used in a clinical setting. Additionally, even though BMI does not provide information on body composition, it's still a good tool that is simple and accurate in determining elevated risk of disease or death for most people. However, the ABSI tool may help people realize that it's not just important to lose weight, but to decrease waist circumference since additional fat concentrated around the midsection has been proven more detrimental to one's health than extra fat around the rest of the body.