Some Restaurants Are Ditching Seed Oils. It Could Cost Them.

Stuart Brioza, a chef and an owner of the acclaimed San Francisco restaurants State Bird Provisions, the Progress and the Anchovy Bar, never imagined that switching kitchen oils could be so political.

Two years ago, he stopped using grapeseed oil in favor of sugar-cane oil, which he thought was less processed and more flavorful, adding a buttery note to vinaigrettes and aiolis.

Mr. Brioza only recently realized that the decision to stop using seed oil aligned him with Robert F. Kennedy Jr., the health secretary, who is known for espousing conspiracy theories about vaccines, fluoride and other public health issues.

Mr. Kennedy and his Make America Healthy Again movement have rallied against seed oils, including canola, soybean and corn oils, declaring — without meaningful scientific evidence — that they are harmful for health.

“I have no association with that movement,” said Mr. Brioza, whose restaurant hosted a fund-raiser for Kamala Harris last year, “or anything that has a funny acronym and rhymes with MAGA.”