Are hot dogs junk food? In the London subway system, they are.

British comedian Ed Gamble had to remove a picture of a hot dog from a poster promoting his comedy show because the city prohibits junk food advertising within its transit system.

But the new poster, which features a cucumber stand-in, turned out to be comedy gold and netted Gamble worldwide publicity.

As The Associated Press reported, “The poster for the show, ‘Hot Diggity Dog,’ showed a mustard- and ketchup-smeared Gamble beside a half-eaten hot dog on a plate.” Gamble’s show kicked off in February and has been promoted with what can only be described as meat themes. According to the promoter, “Ed Gamble has minced a load of meat (thoughts), piped it into a casing (show) and it’s coming to a bun (venue) near you. There will be all your classic Gamble ranting, raving and spluttering but he’s doing fine mentally. Promise.”

This may be in part because the comedian is also known for a podcast called “Off Menu,” which features witty discussion about food.

The hot dog promotion fit in perfectly with Gamble’s brand, but not with the London transit system, which, since 2019, has banned advertising of products deemed junk food, defined as “food and drink high in fat, salt and sugar,” according to the BBC. The ban includes not just subways, but also taxis, buses and bus shelters. It was part of London Mayor Sadiq Khan’s effort to address childhood obesity, which he has called a “ticking time bomb.”

American fans of hot dogs, however, might take offense at the designation of the iconic American treat as junk food. In fact, a study published in the Journal of Nutrition in 2022 conceded that there is no universal definition of what junk food is, although the term is generally used to define highly processed foods and those devoid of nutrition.

While makers of sausages and wieners have introduced somewhat healthier options in recent years, the U.S. government’s dietary guidelines note that hot dogs, like sausage and bacon, are high in saturated fat and recommend that Americans eat no more than 10% of their daily calories from these sources.

Additionally, the meat (which could contain beef, turkey or pork, or any combination thereof) often contains preservatives, and the World Health Organization considers hot dogs and other processed meats carcinogens. One study, published in 2021, ranked 5,800 foods by their nutritional profile and found that hot dogs were the least healthy of all foods considered.

That said, the National Hot Dog and Sausage Council says that Americans buy about 9 billion hot dogs a year, and about 10% of hot dogs are consumed at ball parks. As for hot dogs’ famously mysterious ingredients, the council says, “Meats used in hot dogs come from the muscle of the animal and looks much like what you buy in the grocer’s case. Other ingredients include water, curing agents and spices, such as garlic, salt, sugar, ground mustard, nutmeg, coriander and white pepper.”

It’s unclear whether Gamble, who has diabetes, is a big fan of hot dogs himself, although he jokingly told The Guardian that he spends 80% of his time thinking about food. The Associated Press said that he took the change to his poster in stride and that he understood the reasons for the ban on junk food advertising.

“But the new posters promote something way more harmful — the idea that cucumbers pair well with ketchup and mustard,” he said.