The fiery red-headed singer is no exception to being a dramatic weight loss case. However Nicole puts this down to having a fast metabolism and iron deficiency anaemia, a disorder that affects the body's red blood cells and can leave sufferers experiencing extreme fatigue and feeling faint.

She said in an interview: "I've always had a very fast metabolism and I never put on an ounce of weight. But it was getting beyond a joke - I knew I wasn't eating a healthy diet. I hated demanding food before a performance and felt bad about putting people out, so I stopped asking".