The singer lost 30 pounds by reportedly using a meal-delivery plan called FreshDiet, where calorie-controlled meals were delivered to her.
Of course, it also looks like she put in some serious sweat sessions, too, but The Voice judge recently said that she isn't super stressed about her workouts.
"If I can squeeze in a workout, great...if not, that's OK, too," she told ABC News.
Still, it looks like whatever XTina is doing, it's working well...maybe a little too well for fans' liking.
"Christina Aguilera was hotter before she lost her weight. Now she's too skinny and blah," one fan tweeted.
"I freaking love Christina Aguilera, but she is too skinny and at times she looks sick," another chimed in.
"It appears as if she has taken her dieting to the extreme – totally unnecessary as she has (or did have) curves – something increasingly lacking in Hollywood," a doctor revealed to RadarOnline.
"Her wrists and arms are much thinner than they were – which will put her at an increased risk for bone loss," he explained.
This isn't the first time the singer has been called out for being "too thin." Back during her "Genie In a Bottle" days, she faced similar criticism.
What do you guys think? Has she lost too much weight?