Page Six got their hands on a copy of the profile featured in the autumn issue of the Net-A-Porter magazine, and report that Stewart doesn't hold back.

Stewart told the magazine Gwyneth Paltrow, founder of lifestyle blog and e-commerce store Goop, should stop trying to be like her, and stick to acting.

"She just needs to be quiet. She's a movie star. If she were confident in her acting, she wouldn't be trying to be Martha Stewart," she said.

Stewart says actress Blake Lively went to her for advice before launching her own lifestyle website Preserve.

Stopping short of insulting Lively herself, Stewart's senior vice-president Kevin Sharkey had some choice remarks about the Gossip Girl's latest venture instead.

"I don't get the sense she's credible," says Sharkey. "She's enthusiastic, but she's not credible."

Stewart didn't hold back her opinion of Lively's blog earlier in the year.

When she was asked by the Huffington Post in July what she thought about Lively becoming "the next Martha Stewart" the lifestyle guru said: "Let her try.

"I don't mean that facetiously! I mean, it's stupid, she could be an actress! Why would you want to be me if you could be an actress?"

Stewart became famous for her lifestyle television show Martha Stewart Living, which she turned into a highly profitable empire which includes a magazine, books, website and product range.

Stewart hasn't limited her criticisms to actresses-turned-lifestyle-bloggers.

In the Porter profile, Stewart also blasts Sheryl Sandberg's book Lean In, which is about helping women make gains in their careers.

"Isn't 'leaning in' spending a lot of time?" said Stewart.

"I think being entrepreneurial is something women should strive for, rather than working up the corporate ladder."

Stewart even took aim at the creators of the Netflix show Orange is the New Black for their choice of Taylor Schilling as lead actress.

"They could have done that so much better. That girl is not good enough, the lead actress," said Stewart.

"I met the real Piper [Kerman]. She was in prison either the same time or after me, and I talked to her about it."

Stewart served five months in jail 10 years ago for obstructing justice in her insider trading investigation.

She says she felt sorry for her fellow female prisoners.

"I feel so sorry for all of them in prison. The system lets them down. It's hideous. And I'm sorry I have not had the time or the real inclination to help, but right now, there is a huge movement against the penal system."