(contactmusic.com) - Lily Allen was forced to adopt healthier lifestyle after being diagnosed with a heart condition. The 22-year-old singer was so shocked when doctors discovered the heart murmur, she vowed to curb her party lifestyle and get fit. Allen immediately hired a personal trainer and succeeded in losing nearly one and a half stone (9.5 kilograms) - dropping three dress sizes in just six weeks. But the Smile hitmaker insists she lost the weight for health reasons and not a desire to fit in with other extra slim celebrities. She says, "I found out three months ago. I have been asthmatic all my life but this was really quite scary. When they asked me how much exercise I did, I had to be honest and say hardly any. "I used to love nothing more than sitting in front of the telly with two packets of Ginger Nuts (biscuits) and two bags of milk bottle sweets and I would devour the lot. But this heart thing made me cut back on that kind of crap. I haven't done this because I wanted to be a skinny minnie."