"Janet's breathing a huge sigh of relief and has gone into snack attack mode, eating everything she wants in large amounts," an insider told Radar.
"She's starved herself this past year so she could look good on stage on those skimpy outfits and it paid off."
Jackson's "State of the World" tour was a huge success, pulling in at least $33 million dollars. But the insider reveals the 52-year-old was miserable throughout, because she wasn't able to eat her favorite foods.
"Now she's enjoying Mexican food, pizza, sushi, pasta, donuts, sugary cereals, M&Ms, all the things she loves," the insider said. "But it's all gone to her waist, butt and thighs.
"She's put on 30 pounds at least!"
Check out Jackson's growing gut in this Radar gallery.
2018 was a stressful year for Jackson that could have led to her weight gain. The "Escapade" singer once said, "I stay away from the scale."
In June, she addressed her battle with depression in an emotional letter for Essence magazine.
"I could analyze the source of my depression forever. Low self-esteem might be rooted in childhood feelings of inferiority," she wrote. "It could relate to failing to meet impossibly high standards. And, of course, there are always the societal issues of racism and sexism. Put it all together and depression is a tenacious and scary condition. Thankfully, I found my way through it."
Jackson credits being a mom with helping her deal with the down times. The star was once the spokesperson for NutriSystem, which promotes weight loss.
As Radar readers know, the singer had a late-in-life baby. She's mother to Eissa Al Mana whom she gave birth to on January 3, 2017 by ex-husband Wissam Al Mana. They had an ugly breakup, and Jackson ditched all her baby weight at that time.
Just days before his death, Janet delivered a powerful message to the famed manager Jackson clan father at the Radio Disney Music Awards.
Janet said her dad "drove me to be the best." She also paid tribute to her ailing mother Katherine by saying that she gave her "the most extravagant love imaginable."
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