More than 600 people, from toddlers to seniors, marched in Napa's first-ever Walk to Cure Diabetes at St. Supery Winery in Rutherford Saturday.

"It was a great day," said Heather Haynes, outreach manager for the Juvenile Diabetes Research Foundation. She had expected only about 400 would show up for the fundraiser.

Many marchers showed their support for young victims of the disease by sporting T-shirts emblazoned with team names such as Jacob's Crew, Hog Dog'n for Amber, the Needle Squadron and Jack the Bean Stalker.

For an hour before a ribbon was cut signaling the start of the two-mile trek, the crowd was entertained by the Napa High School Jazz Band, Violet the Clown and others.

Francisco Castillo of Vallejo donned a superhero costume and was joined by a young Batman and Superman. He vowed to form a "superhero team" for next year's North Bay walk.

Zachary Lee, 10, of Santa Rosa pulled up his shirt to proudly showed his insulin pump. His mother, Theresa, said, "We're looking for a cure for him."

She said the pump device "has made our life better."

"Many people have old and wrong ideas about diabetes," she said. "Some people look down on you as a parent and think you fed your kids wrong (causing the disease)."

Lee's older sibling, Carson, wore a Disney character Goofy costume. "I'm doing it for my brother," he said.

Jack Castleberry of Napa is only 6, but it was his third walk. He was diagnosed with juvenile diabetes at age 3.

Tommy Fox was only 16 months old when diagnosed. "This is our fifth year," his father, Jim Fox, said. The boy has walked in prior events in San Francisco and Sacramento.

"It could happen to anybody," the father said. "Tommy had flu-like symptoms. It turned out it was diabetes. We almost lost him."

Officials said it will be a week or longer before they learn how much was raised by the event. Funds will be used for research that participants hope will someday lead to a cure.

Juvenile diabetes occurs when the body fails to produce insulin, a hormone needed to convert sugar, starches and other food into energy needed for daily life. Once diagnosed with the disease, patients must take insulin for the rest of their lives. Juvenile, or type one, diabetes can lead to devastating complications including kidney failure, blindness, heart disease, stroke and amputations. It can be fatal.

The Rutherford walk was one of 11 similar events already held or scheduled before July 2006 in the Bay Area.

For information about the disease, go online to the Juvenile Diabetes Research Foundation (Greater Bay Area Chapter) Web site at www.jdrf.org/greaterbay.