The scene plays out repeatedly in Dr. George Griffing's office: Big, round bellies come through his exam-room door well before the rest of the patients' bodies.

That's when Griffing, professor of internal medicine at St. Louis University Medical School, pulls out a ruler -- or a yardstick, as the case may be. He has those patients lie flat on their backs on an exam table. Then he measures their Sagittal Abdominal Diameter, which is the height of their bulging midsection from table top to tummy top.

"I'd like to use a ruler, but with a lot of patients I have to use a yardstick," he says. "What we're really looking for is how much fat is in the abdomen and the liver. It's simple and accurate and reveals a lot of information."

Medical experts have long suspected that people with excess deep belly fat are at an increased risk for cardiovascular disease and Type 2 diabetes, and ongoing research bolsters that belief. In 2007, the National Institutes of Health reported that studies at Beth Israel Deaconess Medical Center and Harvard Medical School showed deep belly fat produces higher levels of a protein that appear to reduce insulin sensitivity regardless of age, gender or body mass index.

Griffing believes that measuring abdominal height is more efficient and accurate at predicting the risks of diabetes and cardiovascular disease than more commonly used methods, such as calculating body mass indexes or measuring the circumference of patients' waists.

Though not yet standardized, Griffing says, studies have found that abdominal heights that measure more than 10 inches in women and more than 12 inches in men triples the chance of cardiovascular disease.

Patient Tom Groll, 59, recently dropped about 5 pounds, most of it from his abdomen. His abdominal height has decreased from 14 inches to 12 inches, and his blood sugar levels have dropped from about 180 to 160, which means he's getting his diabetes under control.

Both the American Diabetes Association and the American Heart Association endorse using the midsection measuring technique. On its Web site, the American Diabetes Association calls it a simple, cheap and noninvasive tool, but added that more research is needed.

sunday@tribune.com