“Investigating their state’s notoriety as a ‘stone area,’ two University of North Carolina doctors reported that too much spinach is a major cause of kidney stones.
“The stones are caused by excess oxalic acid in the diet, said researchers James C. Andrews and Claude L. Yarbro, and the ‘much-praised spinach is one of the worst offenders.’ “
– From Time magazine, April 9, 1956
Andrews and Yarbro were onto something, if not quite as much as they thought. More recent research has turned to the South’s taste for high-fat foods and its hot weather, a contributor to dehydration.