The 32-year-old actress, who raises daughters Honor, 5, and Haven, 2, regrets being so hard on herself, reported People magazine.
"I was a lot more critical of my body when it was probably pretty awesome. Why did I not ever wear jean shorts? That's so crazy. I was so skinny. I didn't have any cellulite... What was I thinking?," Alba told Health magazine.
The actress, however, is more accepting of her body following the birth of her two children.
"Now I'm a lot more confident in my skin - because who cares? At the end of the day, it's so much time spent on something that really doesn't matter that much.