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She stated, "The hardest thing was losing weight and practicing the song." She added, "Everyday, I felt like I was going to faint. But I didn't."

Despite her fatigue, Ailee's hard work seems to have pulled off. Not only was she able to showcase her ever amazing vocals but she also displayed an image transformation with a slimmer body. Ailee revealed that she had actually lost 10 kg (~ 22 lbs) and explained her diet, saying, "I ate 500 calories each time." She elaborated, "100 grams of proteins like shrimp, beef, chicken breast, or crab meat; a little bit of vegetables; and one fruit per meal."

The result? "In a little over one month, I lost weight," she revealed.  After surprising the crowd with her revelation, she added, "I didn't intend to lose weight so suddenly; I just lost weight suddenly."