Ford tipped the scales at 330 pounds Monday morning as he called on his fellow mayors across North America to join him in a six-month weight loss campaign.
"I know that the city of Toronto will lose more weight than any other city in North America," the mayor said in a news conference to kick off the program.
Dubbed the "Cut The Waist Challenge," the campaign aims to encourage the public to embrace a healthier lifestyle, said the mayor, who hopes to lose 50 pounds by June 18.
The campaign got mixed reviews online, with some on social media sites accusing the mayor of launching the program to distract from impending budget cuts.
Others cheered for the mayor and his brother, wishing them luck and offering advice on how to slim down.
But it remains unclear how many of Ford's peers will take him up on the challenge, given that some are already known for their healthy habits and lean physique.
In a tweet announcing the program, Ford singled out Calgary Mayor Naheed Nenshi, Vancouver Mayor Gregor Robertson and Halifax Mayor Peter Kelly, as well as New York City's Michael Bloomberg and Chicago's Rahm Emanuel.
"Mayor Bloomberg exercises daily and very avidly watches what he eats — two reasons why he's about as thin as he was in college 50 years ago and not at all overweight," Bloomberg's spokesman, Stu Loeser, said in an email.
"Though this plan sounds like a great idea, it doesn't really apply to our mayor," he added.
Kelly also declined to take part in the program, saying he can't afford to lose more weight after dropping 30 pounds over the last few years.
"If (Ford) is 330 pounds, he's more than twice my weight, so I think if I went into this challenge, you wouldn't be able to see me," he said.
Emanuel, a trim triathlete who logs daily workouts and carries a water bottle wherever he goes, may not have much to lose either.
Daorcey Le Bray, a spokesman for Nenshi, said the Calgary mayor has his own plans to promote healthy living.
Meanwhile, Robertson's website describes him as "a dedicated cyclist."
Another Ford tweet later in the day noted the challenge is open to everyone, not just elected officials.
But not everyone is buying into the mayor's healthy living message given proposed cuts to the city's budget.
"The mayor's Cut The Waist program would seem much more genuine if it wasn't happening two days before the budget vote, where 'waste' = services," community organizer and bike advocate Dave Meslin wrote on Twitter.
Ford said he hatched his weight loss plan over the holidays.
"It's the heaviest I've ever been," the mayor said. "I've got young children. This is not healthy. You can't be running the city, you can't be doing all this at 330 pounds."
Ford has joked in the past about being "300 pounds of fun," but as he stepped on the scale in front of a modest crowd Monday morning, some teased that his estimate fell short of the true number.
The mayor's brother, Coun. Doug Ford, signed up for the program and weighed in at 275 pounds.
The brothers patted each other down before the weigh-in to ensure neither carried anything that could throw off the results.
The mayor said his weight loss plan will be based on "common sense" — more exercise and less food.
Ford has admitted to having a weak spot for late-night snacks, particularly ice cream.
The mayor has also drawn the ire of cyclists and runners alike by arguing they clog the streets and contribute to traffic jams.
Both Fords will check their progress with a public weigh-in every Monday morning on a large scale at city hall.
The mayor says eventually he'd like to make it down to 225 pounds.
Toronto residents can join as well through an interactive website,www.cutthewaist.ca.
The mayor's predecessor, David Miller, lost roughly 50 pounds while in office by cutting out junk food and adopting a rigorous workout regimen.