The 30-year-old writes in her new book 'I Got This: How I Changed My Ways and Lost What Weighed Me Down' that she turned down a chance to read for the plum role for weight reasons.
In an excerpt from the book published by Uptown Magazine, she said: I had [gained weight] with Effie [in Dreamgirls]' and as much as I was moved by this film, I wanted to try a role that had nothing whatsoever to do with my weight.'
Instead, director Lee Daniels chose then-unknown actress Gabourey Sidibe for the part of Precious, an overweight and abused teen.
The film went on to accrue a plethora of awards and nominations, including six Oscar nods, including a Best Actress nomination for Sidibe.
It would have been Hudson's second Academy Awards honour after winning Best Supporting Actress for Dreamgirls in 2006.
The former American Idol contestant's refusal to read for the role also caused some additional stress for the film's director.
Daniels told The Guardian back in 2009: 'We were weeks away from the shoot but I still hadn't found Precious.'
