Back when he was a child, American University historian Alan Kraut watched a TV biography of public-health pioneer Joseph Goldberger on Cavalcade of America, a ’50s series featuring half-hour tales of American heroism. Decades later, Kraut would begin researching a book on Goldberger—but in one museum and library after another, his efforts to track down a recording of the show came to naught.

Then one day, Kraut went down to interview one of Goldberger’s sons in Austin, Texas. Over lunch, the man offhandedly asked whether Kraut would like to see an old movie about his father. It turned out to be the Cavalcade episode—perhaps the only copy still in existence.

The find was one of many fortunate breaks for Kraut on the way to publishing his fifth book, Goldberger’s War: The Life and Work of a Public Health Crusader—the story of an immigrant who became one of the stars of a then-new field. Goldberger garnered the most fame for solving the mystery of pellagra, a disfiguring and often fatal disease that emerged, with surprising suddenness, in the American South during the early 20th century.

Victims of pellagra would develop severe skin lesions, followed by internal problems, mental disorientation, and, in many cases, death. But as dramatic as the disease’s symptoms were, Kraut was equally captivated by Goldberger’s efforts to battle a scientific consensus that proved to be thoroughly incorrect. “He was asked to investigate a disease that everyone thought was caused by a germ,” Kraut says. “Everyone figured all he needed was to find the critter. Yet he became convinced very quickly that there was no pathogen, and that it had to do instead with lifestyle and diet. But persuading the medical establishment was not easy.”

Goldberger posited that pellagra was caused by poor nutrition—especially a chronic lack of protein that had emerged during the late 1800s, as Southern workers moved from farms to factories and agricultural land was converted from food production to cotton farming. But Goldberger’s carefully controlled studies in orphanages and with prison volunteers were not enough to satisfy many skeptics. Even experiments on his lab workers, his wife, and himself—including the swallowing of scabs, blood, and mucus taken from pellagra sufferers—failed to persuade scientific bigwigs that pellagra wasn’t caused by an infectious agent. And perhaps not surprisingly, many Southerners recoiled from the notion that they didn’t know how to eat.

Slowly, however, opinion came around to Goldberger’s view—though he didn’t win full kudos until after he died of kidney cancer, in 1929. His stock rose after other scientists, over several years, finally fingered the missing nutrient: niacin. “He was arguably either No. 1 or No. 2 in the ranking of American medical heroes until Jonas Salk and Albert Sabin created their polio vaccines in the 1950s,” Kraut says. It was that fame that spawned the Cavalcade episode—along with an MGM movie short and a comic book featuring Goldberger on the cover.

Like Goldberger, Kraut, 56, grew up in New York City and lived much of his professional life in Washington. He has taught at American since 1974, specializing in medicine, immigration, and ethnic history—and to him, Goldberger’s Jewish ancestry, along with his marriage to a well-off New Orleanian descended from Jefferson Davis, added another rich layer of complexity to the Goldberger’s War story. The unlikeliness of such a pairing helped fuel Kraut’s interest, and his research uncovered a wealth of correspondence documenting the tensions spawned by the couple’s courtship, which for its era was highly unconventional.

Not long ago, Kraut gave a speech to a group of physicians in Savannah, Ga., that helped clarify Goldberger’s scientific legacy. He asked how many doctors in the audience felt confident diagnosing a case of pellagra. “Only the oldest physicians raised their hands,” he says. Goldberger, Kraut concluded, had done his job so well that few today even remember why his accomplishment was important. —Louis Jacobson