The Australian actor (40) said in a lengthy Instagram Live video that she had failed to treat her body with “love and respect” in the past.
The Pitch Perfect star who earlier this year set herself a target of reaching 75kg in body weight said she was on her way to developing “self love”.
The actor credited a stay at Austria’s VivaMayr wellness centre with leading her to change her diet and start exercising more.
“I wrote a little letter to myself about how I’m really gonna give it my all this year, and then I did,” she said.
In the video, Wilson also revealed that she has been consuming under 1,500 calories a day while exercising “like a beast”.
She said: “Nutritionally, the only thing is I do try to stay under 1,500 calories because of my body type. If want to lose weight in that week, I kind of have to stay under the 1,500 each day.”