Unless Americans start exercising more, they’ll continue to get fatter — and sicker, according to a national health leader who’ll be speaking in central Iowa today. Dr. Gene Barrett is president-elect of the American Diabetes Association and is director of the University of Virginia Diabetes Center. He says diabetes is often the result of a lazy lifestyle.Dr. Barrett is giving a noon address at Des Moines University. Barrett is a professor of medicine and pediatrics in Charlottesville, Virginia, and his son is diabetic. He says a lot of our current problem with diabetes is related to changes in our eating and exercise patterns. He says many more of us are working indoors at computers now instead of getting outdoors and doing something physical.Some 170-thousand Iowans have diabetes. Nationwide, the number of diabetics has risen 25-percent just in the past decade. He says because of how diabetes tracks obesity, experts expect diabetes to effect 20-percent of the entire U.S. population within the next 15 years. It’s currently in about six-percent of Americans or 17-million people, while another 16-million are considered pre-diabetic, with elevated blood glucose levels that aren’t high enough to be diagnosed as type-2 diabetes. Barrett says the disorder cost about 120-billion dollars to treat last year in the U.S. alone. In general, people with diabetes spend two-to-three times more of their income for health insurance and out-of-pocket costs for their health care. He says the average person will spend three-to-four-thousand dollars a year for health care, while a diabetic may spend six-to-12-thousand dollars.