15. Christina Aguilera
Christina Aguilera gained quite a bit of weight while pregnant with her second child, but after the baby was born, she focused on losing around 30 pounds of extra baby weight. Although she’s proud of her body no matter what size she wears, she admitted feeling really happy about reaching a slimmer figure ahead of her return to The Voice. The transformation didn’t just change her look—it also gave her a boost in confidence and energy, helping her take on the fast-paced demands of being a coach on the popular show.