"I was never really hugely big, but I certainly weighed more than I do now. I ate to sing. If I started to get a bit lumpy round the middle, I would start thinking, 'Well, I must get it off,' but I was also aware of how much I couldn't or shouldn't take off."
Dame Kiri began her training under Sister Mary Leo, DBE, RSM, at Saint Mary's College. At 21, she moved to London and her professional career quickly took off and, since the 1960s, Dame Kiri has been a leading international soprano.
The singer also said that television talent shows were not likely to produce the next operatic star because there was no such thing as an "overnight success" in the field.
"I've been criticised for even mentioning things like The X Factor, but I'm always wary of someone who is a bus driver and decides, aged 28, that they want to be a singer," she said.