Now she's opened up about her transformation and revealed some surprising details about her journey.
The Pitch Perfect star sat down for a virtual interview on The Drew Barrymore Show and lifted the lid on her inspiring health drive.
"So the last few years I’ve been theming my years," she explained. "So like, the 'year of fun', last year I had the 'year of love' and then this year, I was like, it's going to be the 'year of heath'."
WATCH: Rebel Wilson opens up about weight loss and why she transformed her health
Rebel said turning 40 in March was an eye-opener for her and made her realise she had never really focused on her health.
"I was going all around the world, jet-setting everywhere and eating a ton of sugar," Rebel admitted. "That was my vice. I have a very sweet tooth. I love desserts.
"And I've tried, like so many women out there, I've tried fads and diets and things before and I’m like, I need to do a really holistic approach to this, this time."
While her career was going from strength to strength Rebel surprised fans by revealing fame was fuelling her overeating.
Rebel revealed fame fuelled her to emotionally eat
"I think what I mainly suffered from was emotional eating and dealing with the stress of becoming famous internationally - there is a lot of stressful stuff that comes with it - and I guess my way of dealing with it was eating donuts."
Rebel realised she had to work on her mental health to improve her body too.
"So I was working on the mental side of things and thinking why was I doing that? And why wasn't I valuing myself and having better self-worth?"
Rebel's confidence has soared
She also changed her eating habits and learned how to fuel her body in a nutritious and healthy way.
"My diet was mainly all carbs," Rebel said. "Which were delicious but for my body type I needed to eat a lot more protein."
She then added: "So I've lost, I think it’s like 40lbs this year so far and I want to lose a few more."
Rebel has also found love with Jacob Busch
The audience applauded Rebel, who looked very glamorous, for the interview.
It's not just her health which has benefited from her new outlook on life as this year she's also launched her career as a children’s book author and landed her first role in a non-comedic movie.
Rebel is certainly on a roll!
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