The star, who shot to fame in 1999 after her stint on The Big Breakfast, admitted that her early modelling was "probably not great".
The Piranha 3D actress appeared in tabloids when she was 16 years old in the mid-1990s.
"Of course I look back on it and think there was something about it that was... I was very young," she told Stella.
"It was good money but, yes, to have someone of that age posing like that... I think that's probably not great."
Brook added: "I don't think I [felt that way at the time] but I didn't do it for very long anyway."
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