The Nasty singer speaks about her relationship with her late older brother, as well as her personal battles with weight fluctuation in a new two-part documentary series Janet Jackson.
Janet, 55, revealed: "There were times when Mike used to tease me and call me names. 'Pig, horse, slaughter hog, cow.'
"He would laugh about it and I'd laugh too, but then there was somewhere down inside that it would hurt.
"When you have somebody say you're too heavy, it affects you."
Watch: Janet Jackson reveals what helped her through Super Bowl scandal
The actor and singer — who grew up in the spotlight as the youngest member of the Jackson family — added "I'm an emotional eater, so when I get stressed or something is really bothering me, it comforts me."
Janet said she and her older brother — who died in 2009 aged 50 — drifted apart as they grew older, starting with the release of his album Thriller in 1982.
She revealed: "I remember really loving the Thriller album but for the first time in my life I felt it was different between us, a shift was happening.
"That's the time Mike and I started going our separate ways. He just wasn't as fun as he used to be."
And when they worked together on 1995 song Scream she felt frozen out by him.
Janet said: "Michael shot nights, I shot days. His record company would block off his set so I couldn't see what was going on. They didn't want me on set.
"That really hurt me because I felt I was there fighting the fight with him, not to battle him. I wanted it to feel like old times between he and I, and it didn't. Old times had long passed."
Michael Jackson was first accused of child sex abuse in 1993 and Janet said she was upset at the personal cost to her.
She said: "It was frustrating for me. We have our own separate lives and even though he's my brother, that has nothing to do with me.
"But I wanted to be there for him, to support him as much as I possibly could."
Janet claimed that after Michael paid a settlement pay-out to the family of 13-year-old Jordan Chandler, who alleged the singer molested him at his Neverland ranch in California, she lost out on a big deal with Coco-Cola.
She said: "When that came out, Coca-Cola said, 'No, thank you'. Guilty by association. That's what they call it, right?"
The new four-hour documentary has been filmed over five years and will include "never-before-seen footage" from her childhood and a look at her relationship with notoriously strict father, Joe Jackson.
The two-part show — which coincides with the 40th anniversary of her 1982 eponymous debut album — will also feature home videos of Janet and her five-year-old son Eissa Al Mana.
Janet Jackson will air in the UK on Sky Documentaries and streaming service NOW on Monday 31 January 2022.
Watch: Janet Jackson addresses Michael Jackson child abuse allegations in the documentary