Among all the things that help shape a New York City mayor’s image, it’s not always the most consequential topics that tend to stick — especially on matters that concern food.

Just ask Mayor Bill de Blasio.

On second thought, maybe don’t ask him: Mr. de Blasio is still remembered for making the mistake of eating a slice at Goodfella’s, a popular pizzeria on Staten Island, with a knife and fork. It was his second week in office.

Food can be a strangely unifying or divisive factor in New York City politics, with people taking sides on pizza slices, deli choices and, of course, bagels.

That remains true even now, with New York City in crisis, and the mayor’s race perhaps the most important in a generation. Yet with the pandemic forcing much of the campaign inside and online, discussing food — and consuming it at sporadic in-person campaign events — has been a pleasant diversion.

Andrew Yang, the former presidential hopeful, keeps a photo diary of his campaign snacks on Twitter: gourmet pickles on the Lower East Side of Manhattan; pizza at Gino’s restaurant in Bay Ridge in Brooklyn; Dominican food in Hunts Point in the Bronx.

When Mr. Yang stopped recently for soup dumplings and scallion pancakes in Chinatown, he said that he wanted to highlight restaurants that are struggling during the pandemic.

“As much as I enjoyed running for president, the culinary options of New York City are very different than those in Iowa and New Hampshire,” he said. “It’s been delightful for me to think of a type of a food that I want, and it’s available.”

Mr. Yang is not the only candidate dining al fresco.

After Mr. Yang posted a photo of his lunch with Donovan Richards, the Queens borough president, at Szechuan Mountain House in January, Maya Wiley soon followed with news of having had “slammin’ chicken wings” with Mr. Richards at Queens Bully, a gastro pub.

Even before she entered the race, Ms. Wiley, a former MSNBC analyst and ex-counsel to Mr. de Blasio, posted a photo last summer of her Caribbean meal at Code Red in the Bronx with Carl Heastie, the State Assembly speaker — a coveted ally who has not made an endorsement yet.

Eating on the campaign trail can be trickier for Eric Adams, the Brooklyn borough president, who is a vegan evangelist and often brings his own food. He grabbed a green goddess smoothie and a quinoa tofu bowl one recent morning before visiting Yankee Stadium in the Bronx to hand out masks.

“This will be in the car so I can have healthy options, and I don’t have to nibble on something unhealthy,” he said.

For Mr. Adams, his personal transformation from an overweight police officer in the 1990s to a lean vegan who loves yoga and meditation is a key part of his campaign narrative. Mr. Adams published a book last year called “Healthy at Last” about his plant-based diet, with recipes for tempeh stir-fry and jackfruit and okra gumbo.

Mr. Adams is serious about his diet after dropping 30 pounds and reversing his diabetes. He has a mental map of the best vegan spots around the city, name-dropping Screamer’s Pizzeria in Williamsburg in Brooklyn, and boasts of his homemade creations like pizza with a cauliflower crust.

When Michael R. Bloomberg was mayor, he famously cracked down on trans fats, sugary drinks and salt to try to force New Yorkers to get healthy. But his personal diet was filled with indulgences: He sprinkled salt on bagels and pizza, and enjoyed burned bacon and peanut butter sandwiches, Cheez-Its and Big Macs.

Mr. Adams also wants to make public health a focus of his administration if elected, but would undoubtedly be a better model in his personal habits than Mr. Bloomberg.

In his book, Mr. Adams describes waking up with vision problems in March 2016 and learning he had diabetes. After years of eating fast food like McDonald’s and KFC, Mr. Adams decided to change his lifestyle, along with his partner, Tracey Collins, a former school principal.

The book has plenty of practical advice: “Don’t Brag (When You Start Looking Oh So Good)” and discusses health disparities in the Black community.

Now when Mr. Adams eats with community leaders, he first scans the menu for appetizers and side dishes and orders something simple like broccoli or hummus. If he is offered something homemade, he tries to be polite.

“I’m a master at moving food around on the plate,” he said with a laugh.

Mr. Adams isn’t even the only candidate with a cookbook: Scott M. Stringer, the city comptroller, published one on healthy eating in East Harlem in 2008. But Mr. Stringer is no expert home chef. His contribution to the book was a list of ten tips for ordering takeout, including, “That’s dressing on the side, please.”

Mr. Stringer said he learned some kitchen basics after marrying his wife, Elyse Buxbaum, in 2010.

“Pre-Elyse, I was a connoisseur of West Side takeout,” he said. “Now I’m proud to say that I’m getting better at cooking. I can make pasta and throw tomato sauce on it.”

Asked about his best meal on the campaign trail, Mr. Stringer sounded crestfallen that he remains mostly stuck inside his bedroom closet on video chats.

“Takeout sushi in the midst of Zooming,” he said.

The silver lining, perhaps, is avoiding the pitfalls awaiting candidates when they make public food choices.

For instance, a recent stop for a dan tat, a Chinese egg tart, got Mr. Yang into trouble with his wife, Evelyn.

“It was warm and delicious,” he said. “The only problem was that I didn’t bring one home for Evelyn. She saw it on my Twitter feed.”

As for Mr. de Blasio, wisdom has not necessarily come with experience. Six years after the pizza fiasco, the mayor suggested that his favorite New York City bagel came toasted — prompting many bagel aficionados to recoil in horror. To make matters worse, Mr. de Blasio’s bagel purveyor of choice did not even have a toaster.