Rebel Wilson "never thought" she could lose weight.

The 44-year-old actress famously shed 77 pounds in 2020 following a course of intense diet and exercise but admitted that once she did manage to go on a health kick, she regretted not doing it sooner.

She told Britain's OK! Magazine: "I never thought I could do it. Then in 2020, when I just really focused and did it, I felt sadness, because I’m like, 'I’m 40. Why did I not do it 10, 20 years ago?' I felt like this sadness, that I’d hidden away from people and from relationships."

The 'Pitch Perfect' actress has been looking back on her life so far as part of her memoir 'Rebel Rising' and noted that now was the right time to do it because she can truly reflect on her journey to Hollywood stardom rather than writing what she thinks would be a "boring book" about her body transformation.

She said: "In 2020, I did this experiment called “the year of health”. And I lost a lot of weight. That garnered more attention than any movie I’d ever done. Then I got an offer to write a book about it. It was going to be “my year of health” but when I got into thinking about my relationship with food and emotional eating I thought, “Well, there’s so many things about my life and past that go into this. And it’s boring to write a book about, ‘Yeah, I exercise for two-and-a-half hours a day and drink eight glasses of water…’”

The 'Senior Year' star recalled not being able to "stand up" for herself at times when she was younger and would turn to food as a comfort as she ended up in a vicious cycle of "trashing" her own body.

She said: "Being born a girl where I came from in Australia, I didn’t stand up for myself sometimes. Or I was told to just shut up and be a good girl. Then, because I didn’t feel that I was any good, I was feeding myself food that wasn’t good. And it was like this whole cycle of like, 'Oh well, I’ll just trash my own body.'"