And he is pointing the finger of blame at his daughter, Liz Wheatcroft.
Tony thought he was doing mother-of-two Liz a favour last year, when he agreed to join in her mission to lose weight.
Liz, 35, had just had her second child, was feeling overweight and under-confident.
She did not want to go to a slimming club on her own, so she persuaded her overweight dad to go with her.
What 65-year-old Tony, of Sowerby, did not know was that Liz had ulterior motives. She and her mum, Anne, desperately wanted him to lose weight. He once weighed 23 stones and they were worried about his health.
Tony is not complaining because he has shed four and a half stones with the healthy eating group. He is now down to 16st 7lb and has had to buy a new wardrobe after reducing his waist size by a whopping 12 inches.
Liz, who lives in Hipperholme and teaches at Holywell Green Primary School, is also back to her normal, cheerful self after losing two-and-a-half stones and hitting a size 10. She says she cannot remember ever being that size, even as a teenager and, like her dad, says she has no intention of ever putting it back on.
Liz, who has two children, three-year-old Dougie and one-year-old Millie has attended Avis Burston's WeightWatchers class at Christ Church, Hipperholme, with her dad for the past 12 months.
"I was feeling really down after having Millie and did not want to go to class on my own, so I spoke to my mum who thought taking dad with me was a brilliant idea. He didn't take much persuading because he has tried to lose weight lots of times on his own, without much luck," she says.
She says they have helped one another stay on track and if she had gone on her own, she might have given up long ago.
Tony, who was the only man in class for the first few months, says he is amazed how easy losing weight has been. "I think being with like-minded people helps and staying for the talk is really useful", he says.
The two are both still attending classes and are not the only family members to benefit from being slimmer and healthier. Meanwhile, Anne has also been following Tony's healthy-eating regime and lost weight.
Avis Burston says men are often embarrassed to come to a class on their own, so coming with another family member is a good idea.
"I'm really proud of Liz and Tony's achievements. They don't just look better they feel it too, and I'm pleased to hear Tony has now forgiven Liz for misleading him a little!"