Natalie Cassidy has revealed she was paid £100k to lose four stone for a fitness DVD but regained the weight two months later after bingeing on her favourite foods.
The EastEnders' star released top-selling weight-loss DVD Then and Now in 2007 and The Perfect Ten in 2013.
But she has now admitted she regrets having made them.
"I was very overweight and they approached me and said listen, we're going to give you £100,000, we're going to get you really fit and you're going to lose four stone,' she said on the Comfort Eating with Grace Dent podcast. "I was like happy days, let's go for it. I just thought, that's a lot of money; but it wasn't the right thing to do.
"It wasn't," she admitted. "You are losing a lot of weight in a three or four-month period, twelve or sixteen weeks, low calories and training every day.
"I got there, and as soon as that DVD came out, I ate for England. I put all the weight back on in eight weeks."
Despite the regrets, the 39-year-old, who is best known for playing Sonia Fowler in the long-running BBC soap, poked fun at herself by adding that she would "look like a supermodel" if it wasn't for her weakness for mayonnaise.
In February, the actress spoke out about being fat-shamed when she competed on Strictly Come Dancing back in 2009.
The mother-of-one, who was partnered with professional dancer Vincent Simone and finished in fifth place, said she felt ridiculed when she was asked to perform a move that was usually done by male dancers.
She told The Sun : “I was about 4 stone bigger than I am now. Vincenzo was quite little.
“And I remember one week, it was like ‘oh, we’re going to do this dance, but you’re going to pick up Vincent’...
"And I think about it now and I think, 'Oh, that was out of order. It was a bit out of order to me. You couldn't do that now."
Since appearing on Strictly, she has taken on a healthier lifestyle and is trimmer and healthier than ever. She says the key has been a new diet, running and a banning of junk food.
The star, who is engaged to EastEnders cameraman Marc Humphreys, the father of her youngest daughter Joanie, five, told the Daily Express last year that she has “sworn off take-outs.”
She said she had also cut out "cheese, crisps and dips", which she previously said were her "downfall" and reduced her alcohol intake - only drinking white wine in moderation.
