Deborah Voight

The soprano, 46, was fired by the Royal Opera House for being too fat, at a reported 25 stone, to fit into the "little black dress" required for the lead role in Ariadne auf Naxos. Now, after a gastric bypass and 145lb lighter, she has been invited back to the ROH to take the part in their 2008 production

I've always struggled with my weight. When I was eight I went on vacation with my grandparents, who fed me pancakes and steak for breakfast, BLTs, steaks and schnitzels for lunch and dinner. The pounds piled on. When I hit puberty it got progressively worse. Looking back at my life and the emotional side of eating disorders, I can see it coincided with insecurity and self-esteem issues.

I have a sort of addictive personality, and food was my drug of choice. In high school, one of my school counsellors pulled me into her office, saying: "I'm concerned. You're putting on weight and your grades are slipping." I was taking up with my first boyfriend and there were marital problems at home. I'd eat if I was happy, eat if I was sad. I'm a sweet and salty girl - so I'd go for both.

At 24, I heard of a place in southern California where you could have an experimental procedure called a gastric bubble: a bubble is inserted into your stomach that fills up so it's impossible to overeat. I was one of the first to try it. I was desperate. After a month I had differences in my appetite, but it caused nausea, and I couldn't deal with that.

Over the years I tried to lose weight but could never get the bulk of it off. Weight Watchers, Jenny Craig, South Beach Diet, I've done them all. My most successful weight loss was in the 1990s when I took an appetite suppressant called Phen-phen, which became a craze in the US. I lost 60lb. But when the Food and Drug Administration made an announcement to do with heart issues around it, it was taken off the market. My weight all came back, and some.

In 2003, when I was going to sing at Covent Garden, I'd already had a consultation with a surgeon about a gastric bypass. I knew my voice was stunning but I wasn't enjoying it. I had the energy to get through rehearsals and performances but that was it. I had ?no energy for the rest of life - certainly nothing physical. And I was having trouble with my knees. Heart disease is a factor in my genetics, so it was just a matter of time before I was in trouble.

All I needed was time in my schedule to go into hospital. Covent Garden knew what I looked like - I'd already sung there twice. I certainly didn't need to hear from them that I was fat. But lo and behold, when they cancelled me, I had this chunk of free time. After the surgery I started by eating minuscule amounts of puréed foods, graduating to easily digestible protein. I had to take care not to fill up on liquids, and you're advised not to drink for 30 minutes prior to and after food. I cancelled just one recital. Six weeks later I was performing.

The first time I cooked a meal for a friend, I made meat loaf and baby carrots. I caught myself thinking: "Who do you think you're feeding?" But after one carrot and a spoonful of meat I felt as though I'd eaten an enormous meal. In June it will be three years, and I can eat pretty much anything, but I don't touch alcohol. I concentrate on protein. Food isn't as important as it was. But when you have an eating disorder, those emotional and personal issues still exist, even if, like me, you've lost 145lb. You have to keep working on them.

Losing weight has altered my thinking about how I sing. It's much more physical now. I used to have enormous girth, so when I took a breath all of those muscles would just expand naturally and engage my abdominal support system. Now I have to work harder. I can't rely on nature. I do Pilates and I'm in the gym all the time. When I sang Salome in Chicago, the physical aspects of the role were incredible. I've never worked so hard on stage in my life! Aside from the veil dance, I was swinging from ropes, running, jumping, climbing up a cage like a wild animal. I loved it. Salome was extremely liberating - it was the most rewarding experience of my career. I was the size I should be, with the right vocal heft. I felt like a complete artist.Shopping is becoming more fun. But I still think of myself as a large woman, even though I'm a size 12-14. I always used to shop in specialist large-ladies' stores. If something wasn't perfect I would buy it anyway. Now I just put it back. My biggest fear was running out of huge pantyhose, especially in Europe, where they're difficult to find. I almost fainted the other day when I shimmied into a pair of Donna Karan jeans.

Opera is changing: today it has to be believable. I don't know where the saying "The opera's not over until the fat lady sings" comes from - it's an appalling statement! But I spent most of my career as that fat lady. And seeing pictures of myself as I was, I wouldn't have cast myself as Salome, or as Helen of Troy - the most beautiful woman in the world - which I'm now singing at the Met, New York. I've gone through a huge emotional life change to get where I am today. But I wouldn't advise anyone to have surgery. It's the last resort s

Deborah sings at London's Barbican on June 9, in their Great Performers series.

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