Since Kate Riedl’s documentary “The Man Who Saved a Million Brains” aired on Australia’s ABC channel in 2005, the country has seen a huge spike—75 percent—in iodized salt sales. Riedl’s film chronicles Professor Cres Eastman’s fight against Iodine Deficiency Disorder, a disease that can cause retardation, deafness, and skeletal and superficial deformation.

Riedl’s will be one of 15 contemporary documentaries screening in Cambridge this weekend as part of the United Nations Association Traveling Film Festival. The films, chosen from around 400 submissions last October, deal with present-day issues around the world—from civil war in Colombia and the aftermath of the 2004 Indian Ocean tsunami to an HIV-positive orphan in China and a group of Sierra Leonean refugee musicians.

The opening screening will take place at the Kennedy School of Government. The subsequent 14 films, grouped into six thematic sessions, will play at the Brattle Theatre this weekend. Seven of the filmmakers will attend their screenings and answer questions about their work.

The festival—presented in Boston by the United Nations Association of Greater Boston and the Kennedy School’s New England Alumni Association—embarks each year from Stanford University, where it was founded 10 years ago by Jasmina Bojic, a filmmaker, critic, and professor at Stanford.

“Documentary, in particular the images, can influence people to think about the world in different ways,” Bojic says. The festival, she adds, is meant “to spark discussion and ideas” in people, while enabling them “to discuss the topics with filmmakers.”

Among the filmmakers attending will be Shui-Bo Wang, whose “They Chose China” tells the story of 21 American soldiers who were POWs in the Korean War and decided to stay in China after being released at the war’s end. The film won the United Nations Association grand jury prize at the festival’s opening ceremonies last fall.

“This film brings the message for peace; [it] is an anti-war film,” Wang says, noting that he has shown the film at festivals in places plagued by violence, like Israel and South Korea.

Wang, who once created propaganda for the Chinese communist party before moving to Canada in 1989, describes his first film, “Sunrise Over Tiananmen Square,” as autobiographical, illustrating the evolution of his views away from what he refers to as “the Red Dream.”

Wang says that the film was not released in China because of its short form. But he also speculates that its depiction of political clashes, the opium war, and the 1989 student massacre at Tiananmen Square made it too controversial for the Chinese government’s approval.

Unlike Wang, Riedl is a first-time documentary director.

Riedl, who worked in theater and dramatic film before delving into the genre with “The Man Who Saved a Million Brains,” says she “always had a great love of storytelling...the creation of a world beyond what you know.”

She soon came to favor film because “on so many sensory levels, [it] could capture and take you into that world.”

When Riedl heard about Dr. Eastman’s work on Iodine Deficiency Disorder in Tibet, she sought to bring attention to the little-publicized affliction, especially after learning that the World Health Organization considers the treatment and prevention of the disorder “to be the most significant health advance since small pox” eradication.

“I thought, ‘How could we not know about this!’” Riedl recalls.

And informing the public about lesser-known subjects—such as IDD or POWs who choose not to return home—is part of the festival’s mission.

Documentary “can illuminate the topics in a way that hearing a lecture can’t,” says Erica D. Sanger, program manager at the United Nations Association of Greater Boston and Boston festival coordinator. “It’s the next best thing to being able to talk to the people themselves.”