The former American idol winner has shed loads of weight since meeting her fiance because she wanted to look good for him. Blackstock proposed the 30-year-old 'Already Gone' hitmaker in December last year after just nine months of dating, reported Contactmusic.
"I lost 18 pounds. And I think that happens when you fall in love or date someone. If I am going to be messing around, I got to look good," Clarkson said.
She also said that 'there's not a fad diet'. She worked with a trainer and said halving your portions (meals) does wonders.
"I just cut back my portions, I stopped eating late at night, and I work out a little more than I used to, and I literally dropped 18 pounds in a month. I think it happens when you get really busy. But when I am on my off-time, those 18 might come back," Clarkson added.