Professor’s Salty Suggestion Triggers Tempest in a Teapot

Chemistry professor Michelle Francl didn’t mean to create an international incident.

But her recommendation to put a pinch of salt in tea—a tip offered in her new book, Steeped: The Chemistry of Tea—has stirred up enough tongue-in-cheek trans-Atlantic bitterness to revive references to the Boston Tea Party.

Now Francl, who teaches at Bryn Mawr College in Pennsylvania, finds herself making the rounds on British morning shows, sorting through a flood of emails and jotting media interview schedules on the glass-topped desk she uses for helping students with quantum mechanics problems.

“I wrote an academic book for an academic publisher. My chemistry colleagues who drink tea—I knew they were excited about it,” Francl said in an interview. “I did not expect to cause a minor diplomatic incident.”

In the U.K., tea is serious business, and British headlines reflected the uproar. “American scientist reveals her secret to the perfect cup of tea … but adding hot milk and SALT risks leaving Brits at boiling point,” The Daily Mail exclaimed, while The Guardian questioned the “‘Outrageous’ Tea Recipe.”

“I wrote this 240-page book about the chemistry of tea, and people get really hyperfocused on one page: the advice to add salt,” Francl said.

After publishing a paper on tea in Nature Chemistry, Francl spent three years working on the book, reading about 500 papers and drinking roughly 400 cups of tea, she said. The Royal Society of Chemistry published the book Wednesday.

Francl’s research included investigating advice from a Chinese tea master’s eighth-century manuscript, which recommended adding salt to the water. She studied the chemistry behind that, noting that sodium ions in salt block the perception of bitterness, which helps when tea is overbrewed by accident or on purpose to produce more antioxidants.

“I’m trying to ground it all in the science,” Francl said. “And people are just like, ‘Never mind the science, I know how I do my tea.’”

The brewing discontent over the salt suggestion led the U.S. Embassy in London to issue a statement Wednesday.

“Media reports of an American professor’s recipe for the ‘perfect’ cup of tea has landed our special bond with the United Kingdom in hot water,” the embassy posted on X. “Therefore we want to assure the good people of the UK that the unthinkable notion of adding salt to Britain’s national drink is not official United States policy. And never will be.”

However, with a final tease that set off social media comparisons to the Boston tea tensions of 1773, the statement said, “The US Embassy will continue to make tea in the proper way—by microwaving it.”

Prime Minister Rishi Sunak’s Cabinet Office quickly replied, “We appreciate our Special Relationship, however, we must disagree wholeheartedly … Tea can only be made using a kettle.”

Whether the brouhaha benefits tea drinkers remains to be seen. But as of Thursday afternoon, Francl’s Steeped was ranked the No. 2 food science book on Amazon, topped only by Robert Downey Jr.’s Cool Food: Erasing Your Carbon Footprint One Bite at a Time.

“There are other places in the world where people add salt to tea routinely,” Francl said. “I find it funny they consider it this impossible thing, the same as adding ketchup to your tea.”