At a National Pasta Association annual meeting in the 1990s, Harry Balzer of the NPD group offered pasta makers a distinction that was a hopeful one for their product. Mr. Balzer, whose business tracks food consumption trends, said almost without exception, food trends endure and fads do not. At the time he was looking at the recent history of high-flying and hard crashing oat bran products versus the slow-but-steady growth dating from the 1980s that had been enjoyed for pasta.

Mr. Balzer’s commonsense adage has played out again and again since that time, including, thankfully, the ephemeral success of low-carbohydrate products in the early 2000s.

Against this backdrop, though, recent remarks by Darren Seifer, an NPD associate of Mr. Balzer, are sobering. Speaking at the annual meeting of the North American Millers’ Association, Mr. Seifer said 26% of Americans show an interest in gluten-free products. He said it was too early to definitively characterize this interest as trend or fad.

The gluten-free movement hardly has escaped the radar of grain-based foods, and when the low-carbohydrate boom went bust, everyone in grain-based foods knew it was a matter of time before the next anti-bread wave came along. But did it really need to happen so quickly?