The Good Morning Britain star has enlisted the help of personal trainer Sarah Lindsay and reduced his alcohol intake after a summer of overindulging on wine and cheese.
Speaking about his new diet, Piers said: 'I'm going to see a new personal trainer, and unfortunately Celia's taken it all quite seriously.
WATCH: Dr Hilary fat-shames Piers Morgan live on GMB
"So suddenly it's all the good stuff's gone and all the kale's come in and the quinoa and vegetables. A lot of vegetables. A lot of salmon. A lot less Bordeaux - I'm down to one glass a night," he added to The Sun.
"And, well, during the summer, a lot of cheese went down my gullet, and it could stretch to a bottle of red. Quite comfortably ... Depending on the quality, and maybe a little more."
Piers confessed he overindulged on wine and cheese
Piers' diet revelation comes after his journalist wife made him the subject of her latest column for The Telegraph, in which she claimed her husband deserves to be "fat-shamed".
Reading excerpts from her work on Tuesday's GMB, Piers recited: "I have no issue with my husband's GMB co-host calling him a 'chubster' on live television.
"He, like me, is of the belief that a little bit of fat-shaming where it's due can be a good thing, and there's something shameful about the amount of blue cheese and Bordeaux that man's put away over the past six months.
Piers and his wife Celia Walden
"Moreover, the insults will actually help him lose the weight, he rightfully insists. Something our PC GPs might want to bear in mind for their next chubster patient shuffles through the door. I totally agree!"
Celia's column came after the 55-year-old presenter opened up about his weight issues and claimed that he needed to be "shamed" in order to shed some weight, which led to his co-star Susanna Reid jokily labelling him a "chubster".
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