Sam Smith is getting seriously svelte, and he's showing off his impressive weight loss on Instagram.
Smith claims that he's lost over "one stone" (14 pounds) in only two weeks.
The 22-year-old "Stay With Me" singer posted a black-and-white photo of himself holding a book written by nutritionist Amelia Freer, whom he credits for his dietary success.
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"Three weeks ago I met a woman who has completely changed my life," Smith captioned the photo. "[Amelia Freer] has completely transformed my relationship with food. 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."
Eat. Nourish. Glow.: 10 Easy Steps for Losing Weight, Looking Younger & Feeling Healthier was released in January and is Freer's first book.
VIDEO: Sam Smith on GRAMMY Wins -- 'I Feel Like Kate Winslet At the Oscars'
This is shaping up to be Sam Smith's year!
ET caught up with him at the GRAMMYs, and he gushed that winning big at the awards show made him the happiest he's ever been. Check out the video below to see more.