That was about nine years ago, and from then on Mr. Smith, like so many with diabetes, became fixated on his blood sugar. His doctor warned him to control it or the consequences could be dire- he could end up blind or lose a leg. His kidneys could fail.

Mr. Smith, a 43-year-old pastor in Fairmont, Minn., tried hard. When dieting did not work, he began counting carbohydrates, taking pills to lower his blood sugar and pricking his finger several times a day to measure his sugar levels. They remained high, so he agreed to add insulin to his already complicated regimen. Blood sugar was always on his mind.

But in focusing entirely on blood sugar, Mr. Smith ended up neglecting the most important treatment for saving live-lowering the cholesterol level. That protects against heart disease, which eventually kills nearly everyone with diabetes.

He also was missing a second treatment that protects diabetes patients from heart attacks -controlling blood pressure. Mr. Smith assumed everything would be taken care of if he could just lower his blood sugar level.

Blood sugar control is important in diabetes, specialists say. It can help prevent dreaded complications like blindness, amputations and kidney failure. But controlling blood sugar is not enough.

Nearly 73,000 Americans die from diabetes annually, more than from any disease except heart disease, cancer, stroke and pulmonary disease.