"There are a handful of brands that I have 'blacklisted', there are a handful, it's probably like four."
Husband Kurt joked she should "name and shame", prompting Sarah to respond that she "doesn't want to get sued".
In order for Sarah to stop working with a company, she said they needed to "really grind my gears". And those companies on her list may not ever realise she's had her revenge.
"I just keep you in the back of my mind and the best revenge is dominating the competition, so I'll do what you do, but better," she said.
Kurt then claimed there had been a brand that "did wrong by us and one of the people from that brand ended up trying to get a job at one of our friend's companies".
Sarah alleged the brand had "just punched me like a punching bag" to the point that she was encouraged to take legal action.
"Everyone around me was like you need to take this brand to court, they owe you so much money, you've done all these deliverables for them," she said.
Sarah said there was one worker in particular who was "really nasty" and "really hard to work with".
"I had told another brand that I work with, 'You'll never guess what is happening to me with this brand, what the heck,'" she said.
"This girl she tried to get a job with the brand I'm in with, the nice brand, and she's like, 'I've worked with Sarah's Day before on this campaign.'
"Then the owner of the brand who I am friends with called me and she's like, 'Oh my gosh you'll never guess who is trying to get a job.'"
Sarah has more than 2.7 million followers across Instagram and YouTube, where she frequently shares updates about her life.
Back in October she revealed that she was pregnant, explaining in a video how doctors had advised her to terminate the pregnancy because the unborn baby had a "health condition".
But after agonising over the decision for several days, Sarah said nothing in her heart and body made her feel she should terminate.
The health blogger is now is at peace with her unborn baby's condition and said that her son was "designed" for the couple.