SOME relationships run aground on the perilous¹ shoals of money, sex or religion. When Shauna James’s new romance hit the rocks, the culprit was wheat.
　　“I went out with one guy who said I seemed really great but he liked bread too much to date me,” said Ms. James, 41, a writer in Seattle who cannot eat gluten, a protein found in wheat, barley² and rye.
　　Sharing meals has always been an important courtship ritual and a metaphor³ for love. But in an age when many people define themselves by what they will eat and what they won’t, dietary differences can put a strain on a romantic relationship. The culinary camps have become so balkanized that some factions⁵ consider interdietary dating taboo⁶.
　　No-holds-barred carnivores, for example, may share the view of Anthony Bourdain, who wrote in his book “Kitchen Confidential” that “vegetarians⁸, and their Hezbollah-like splinter faction⁴, the vegans ... are the enemy of everything good and decent in the human spirit.”
　　Returning the compliment, many vegetarians say they cannot date anyone who eats meat. Vegans, who avoid eating not just animals but animal-derived products, take it further, shivering at the thought of kissing someone who has even sipped⁹ honey-sweetened tea.
　　Ben Abdalla, 42, a real estate agent in Boca Raton, Fla., said he preferred to date fellow vegetarians because meat eaters smell bad and have low energy.
　　Lisa Romano, 31, a vegan and school psychologist in Belleville, N.Y., said she recently ended a relationship with a man who enjoyed backyard grilling¹⁰. He had no problem searing her vegan burgers alongside his beef patties, but she found the practice unenlightened and disturbing.
　　Her disapproval¹¹ “would have become an issue later even if it wasn’t in the beginning,” Ms. Romano said. “I need someone who is ethically¹³ on the same page.”
　　While some eaters may elevate morality above hedonism, others are suspicious of anyone who does not give in to the pleasure principle.
　　June Deadrick, 40, a lobbyist in Houston, said she would have a hard time loving a man who did not share her fondness for multicourse meals including wild game and artisanal cheeses. “And I’m talking cheese from a cow, not that awful soy stuff,” she said.
　　Judging from postings at food Web sites like chowhound.com and slashfood.com, people seem more willing to date those who restrict their diet for health or religion rather than mere¹⁴ dislike.
　　Typical sentiments included: “Medical and religious issues I can work around as long as the person is sincere and consistent, but flaky, picky cheaters — no way” and “picky eaters are remarkably¹⁵ unsexy.”
　　Jennifer Esposito, 28, an image consultant¹⁶ who lives in Rye Brook¹⁷, N.Y., lived for four years with a man who ate only pizza, noodles with butter and the occasional baked potato.
　　“It was really frustrating¹⁸ because he refused to try anything I made,” she said. They broke up. “Food is a huge part of life,” she said. “It’s something I want to be able to share.”
　　A year ago Ms. Esposito met and married Michael Esposito, 51, who, like her, is an adventurous¹⁹ and omnivorous²⁰ eater. Now, she said, she could not be happier. “A relationship is about giving and receiving, and he loves what I cook, and I love to cook for him,” she said.
　　Food has a strong subconscious²¹ link to love, said Kathryn Zerbe, a psychiatrist²² who specializes in eating disorders²³ at Oregon Health and Science University in Portland. That is why refusing a partner’s food “can feel like rejection,” she said.
　　As with other differences couples face, tolerance²⁴ and compromise are essential at the dinner table, marital²⁵ therapists said. “If you can’t allow your partner to have latitude²⁶ in what he or she eats, then maybe your problem isn’t about food,” said Susan Jaffe, a psychiatrist in Manhattan.
　　Dynise Balcavage, 42, an associate creative director at an advertising²⁷ agency and vegan who lives in Philadelphia, said she has been happily married to her omnivorous husband, John Gatti, 53, for seven years.
　　“We have this little dance we’ve choreographed²⁸ in the kitchen,” she said. She prepares vegan meals and averts²⁹ her eyes when he adds anchovies³⁰ or cheese. And she does not show disapproval when he orders meat in a restaurant.
　　“I’m not a vegangelical,” she said. “He’s an adult and I respect his choices just as he respects mine.”
　　In deference³¹ to his wife, Mr. Gatti has cut back substantially on his meat consumption and no longer eats veal³². For her part, Ms. Balcavage cooks more Italian dishes, her husband’s favorite.
　　In New York City, Yoshie Fruchter and his girlfriend, Leah Koenig, still wrestle³³ with their dietary differences after almost two years together. He is kosher and she is vegetarian⁷. They eat vegetarian meals at her apartment, where he keeps his own set of dishes and utensils³⁴. When eating out they mostly go to kosher restaurants, although they “aren’t known for inspired cuisine,” said Ms. Koenig, 25, who works for a nonprofit environmental group.#p#分页标题#e#
　　Though the couple occasionally visit nonkosher restaurants, Mr. Fruchter, 26, a musician, said he has to order carefully to avoid violating kosher rules. “We’re still figuring out how this is going to work,” he said. “We’re both making sacrifices, which is what you do when you’re in love.”
　　Even couples who have been eating together happily for years can be thrown into disarray³⁵ when one partner suddenly takes up a new diet. After 19 years of marriage, Steve Benson unsettled his wife, Jean, when he announced three years ago that he would no longer eat meat, for ethical¹² reasons.
　　“It had been in my head a long time, but I could have done a better job of talking about it,” said Mr. Benson, 46, a math professor at Lesley University, in Cambridge, Mass. Ms. Benson, who is also 46, and devises grade school curriculums, said she worried her husband would judge her if she continued to eat meat, “but we talked it out and he is not proselytizing³⁶.”
　　Another concern was whether she would be able to cook vegetarian meals that would meet the nutritional³⁷ needs of everyone in the family, including their teenage daughter. “I wanted us all to eat the same thing for pragmatic, household economy reasons, but also because that’s part of being a family,” Ms. Benson said.
　　So, she cooks vegetarian dinners and makes lunches for herself and her daughter that include meat. She and her daughter have “meat parties” when Mr. Benson goes out of town, she said.
　　“There’s this feeling that if we eat the same thing then we are the same thing, and if we don’t, we’re no longer unified,” Dr. Zerbe said. She and Dr. Jaffe said sharing food is an important ritual that enhances relationships. They advise interdietary couples to find meals they can both enjoy. “Or at least a side dish,” Dr. Zerbe said.
　　For people who like to cook, learning to bridge the dietary divide can be an enjoyable puzzle. Ms. James, the gluten-averse writer, eventually found a man who did not love by bread alone. On her first date with Daniel Ahern, in 2006, she told him that she was gluten-free; he saw it as a professional challenge.
　　“As a chef, it has given me the opportunity to experiment with new ingredients to create things she can eat,” said Mr. Ahern, 39, who works at Impromptu³⁸ Wine Bar Cafe in Seattle. Ms. James said she fell in love with him after he made her a gluten-free salad of frisée, poached egg and bacon. They married in September.
　　Since then, Mr. Ahern has given up eating bread at home, though he still eats it when he goes out. For her part, Ms. James has begun eating offal and foie gras, which were once anathema³⁹. “We’ve changed each other,” she said.