PORTLAND — The Preble Street Hunger Initiative on Tuesday will host the Portland premiere of a critically acclaimed film about hunger in America.

“A Place at the Table,” which was a selection of the 2011 Sundance Film Festival, tells the true stories of three people who don’t know where their next meal will come from. That’s a problem that an estimated 50 million Americans face, including 16.7 million children.

Mark Swann, executive director of Preble Street, said hunger has serious economic, social and cultural implications for the country. “But it could be solved once and for all if the American public decides that making healthy food available and affordable is in the best interest of us all,” he said.

More than 200,000 Mainers struggle with food insecurity, more than the combined population of the state’s five largest cities, said Donna Yellen, director of the Preble Street Hunger Initiative.

The first showing of the film at 7 p.m. Tuesday at the downtown Nickelodon theater sold out quickly, but the Nickelodon management agreed to add a second showing at 9:15 p.m. Between the screenings, there will be a panel discussion that will include a chance for the audience to take part in a call to action.

The panel will include Yellen and Swann; Chris Hastedt, public policy director for Maine Equal Justice Partners; Dee Clarke, a mother of three who has experienced food insecurity; Mark Lapping, a professor of planning and public policy at the Edmund S. Muskie School of Public Service at the University of Southern Maine; and the Rev. Dr. Benjamin Shambaugh, dean of The Cathedral Church of St. Luke.

“We’re excited about getting the community engaged in solutions because hunger is unacceptable to us,” Yellen said.

In the film, directors Kristi Jacobson and Lori Silverbush map the concrete steps needed to build a nation where everyone has access to affordable and nutritious food.

“If people want to know why they see long lines of men, women and children wrapped around the corner of our soup kitchen, or why they see lines at food pantries all over our communities, or why our shelter is overflowing, they should see this film,” Yellen said. “The best part is it encourages you to take action. It makes you realize this is something that is solvable. You leave there equipped with the knowledge to take action and change what’s happening in our neighborhoods.”

Tickets to the 9:15 p.m. showing can be ordered online at www.preblestreet.org or bought at the door if available.