Narrator: This is Science Today. Type 2 diabetes is caused by insulin resistance -- your muscles, which normally use insulin to process sugar, don't absorb the insulin put out by your pancreas. About 3 to 5 percent of Americans have type 2. Dr. Ira Goldfine of the University of California, San Francisco says that almost a quarter of adult Americans are insulin resistant to some degree.

Goldfine: But these individuals don't get diabetes, most of them do not get diabetes because they compensate by making additional insulin.

Narrator: So they get along -- for awhile.

Goldfine: The people in the population who are insulin resistant but are not diabetic don't get off scot free. They pay a price. And many of these people get what we call Syndrome X. And they get high blood pressure -- hypertension -- they get lipid disorders, high cholesterol, and they get a very high incidence of coronary artery disease. So a lot of people who aren't diabetic but are insulin resistant are at risk for these serious problems.

Narrator: Goldfine is studying the possible causes of insulin resistance -- and some potential treatments as well. For Science Today, I'm Steve Tokar.