Lisa Creech Bledsoe / Flickr After you hopped off the scale at your last doctor's visit, your physician might have shown you a colorful chart of your body mass index, or BMI.

The index, a measure of body fat based on your weight in relation to your height, can be traced back to the 1830s. Despite its popularity, it's now understood to be a relatively crude measure of fitness.

Now there's finally an alternative — and it solves the biggest problem with the BMI.

On Monday, a team of Mayo Clinic researchers released the Body Volume Indicator, or BVI, a new tool that could transform how we size ourselves up. The measurement is essentially a ratio comparing your total body volume with the volume of your abdomen, a measurement that can be taken manually or using an app.

While it might sound odd, our waists can provide key insight into our health, Jose Medina Inojosa, a preventive cardiology research fellow at the Mayo Clinic, told Business Insider.

Several studies have documented a link between high amounts of abdominal fat and an increased risk of heart disease and diabetes. In a large 2012 study, researchers looked at data from more than 340,000 Europeans and found that people who were overweight and had large waists — 34.5 inches or more for women and 40 inches or more for men — had nearly the same risk of developing Type 2 diabetes as people who were clinically obese.

One of the most perilous pitfalls of BMI is that it doesn't account for fat carried around a person's abdomen. All it measures is height and weight, which is why some lean people with large amounts of muscle can have a BMI that would qualify as "overweight." BVI is an important step toward answering some of these concerns, Medina Inojosa says.

Scientists still aren't sure why excess fat around our middle is connected to negative health outcomes, but they think it has to do with how fat inside the body, known as visceral fat, may interfere with the normal functioning of our internal organs.

Public-health experts have known for years that the BMI isn't a perfect tool for measuring physical fitness and that an improved metric would incorporate waist circumference.

"For health, the issue is not how much you weigh, but how much abdominal fat you have," a 2005 Harvard Medical School blog post said.

To help people more easily assess their BVI, the body-imaging-technology company Select Research created a corresponding app that compares an image of a person taken from the side with an image of them head-on to estimate their BVI.

"By measuring weight and body fat with a focus on the abdomen," Medina Inojosa said, the "BVI offers a new, enhanced potential diagnostic tool."