Karren appears on the business-based BBC reality show alongside Lord Sugar and is often seen giving hopefuls a piece of her mind in the boardroom, as they attempt to impress and outsmart one another.
And now she has used that honesty to speak out about recent Apprentice runner-up Luisa and her risqué behaviour on this year's Celebrity Big Brother.
Luisa - who is up for eviction this week - has been causing a stir in the house by chatting about orgies, licking fellow contestant Dappy's nipple and even suggesting she and Jasmine Waltz should have a 'lesbian game plan' to win.
So it's no surprise that Karren believes Lord Sugar would be more than a little bit shocked.
Speaking about Luisa on this week's episode of The Jonathan Ross Show, Karren said: "I'm just thankful that Alan is in America because if he watched it I think he would have a mild stroke after seeing what's been going on there."
The 44-year-old businesswoman then continued to say that deep down Luisa is an intelligent lady who is unfazed by people's opinions of her.
"Actually underneath it all she is a pretty smart lady and when she says 'I don't care what people think of me' I think she genuinely means it," Karren said. "I think she has mapped out what she wants to do with her life and that's part of it."
However, Karren also believes that the cupcake entrepreneur might have an addiction to being on TV, following her successful stint on The Apprentice last year.
She added: "The thing is if you're in television you can get addicted to being in television and you want to do one thing and another thing and before you know it, all you are is a television celebrity."
Luisa will face the public vote in the show's first eviction tonight (10 January), along with frisky pal Jasmine, Jim Davidson, Evander Holyfield and Liz Jones.
The Jonathan Ross Show, Saturday 11 January, 9.45pm, ITV
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