Sam Slim! Or something like that.

The "Stay With Me" crooner revealed his dramatic (and quick!) weight loss on Instagram Tuesday (March 17) and gushed about the woman who helped him get there.

"Three weeks ago I met a woman who has completely changed my life. Amelia Freer has helped me lose over a stone in 2 weeks and has completely transformed my relationship with food," Sam Smith captioned the photo of himself pointing at her book. "Everyone go check out her incredible book, and start to live healthy. It's not even about weight loss it's about feeling happy in yourself. Love you Amelia & thank you for making me feel so happy inside and out."

For those who need a little help with the weight conversion, a stone equates to 14 pounds, so yep, Sam Smith lost roughly one pound per day over a two-week period. Wow!

It's clear that the singer is super into his health and fitness routine, as he Instagrammed a photo of himself at the gym on Wednesday (March 18), which you can check out below.

Smith had previously been open about his struggle with body image, explaining that it can be difficult for a bigger man in the gay community.

"There’s also a lot of body dysmorphia in the gay community, which means if you’re not toned and skinny it can be awful," he said earlier this month, revealing that he was once bullied.

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