A woman from Cornwall sold her car to pay for specialist surgery to keep her weight down.
Alison Batchelor was "exhausted" by decades of "yo-yo dieting" in which she lost a total of 70 stone - only to put it all back on again.
She believes her experience is common for many women who are trapped in a constant cycle of dieting and weight gain.
Mrs Batchelor had a gastric bypass 18 months ago and is coming to speak to other people who may be interested in the operation at the Duchy Hospital in Truro.
She said: "I've had a lifetime of being on diets and calculated that over the last 40 years I've probably lost between 65 and 70 stone just to put it on again.
"My heaviest was about 16-and-a-half stone. I'd get down to about 11-and-a-half stone but put it back on again."
Mrs Batchelor, 62, from Wadebridge, now weighs 9 stone 10 and said her weight no longer fluctuates.
She opted for a gastric bypass, which reduces the volume of the stomach being used, rather than a gastric band as she thought she might "sabotage" a band by eating too much.
She said: "I woke up one morning and was mentally exhausted with trying to lose weight.
"I told my husband I was going to sell my car and have a gastric bypass. It's a major operation but very successful - I'm totally liberated now."
Mrs Batchelor, who was 60 years old at the time of the surgery, sold her brand new Fiesta and paid £10,500 for the operation.
She described herself as "a serial yo-yo dieter".
She said: "It's extremely common. Trying to lose weight was a very big part of my life. I was happy when I lost it and then something like a holiday would act as a trigger and I would put it all back on.
"It's very easy for people to say you need to eat less and exercise more and that's true, I would do that, but I would turn around and put it all back on again and that's very common."
Mrs Batchelor said the post-operation aftercare had been fantastic and she now stayed at the same weight without dieting.
The open evening at the Duchy will be held on June 19 at 6.30pm. For more information call Tanya on 0330 818 1838.
