The 31-year-old star - who is expecting a child with fiance Eric Johnson - admitted she is experiencing an increased desire for calorie-laden snacks as her due date approaches, but she plans to worry about her pregnancy weight gain once she has settled into being a mother.
She said: "I had a buttered Pop Tart this morning. I'm eating a lot of stuff that I ate in my childhood. Kraft Mac n' Cheese, Pop Tarts, Cap'n Crunch. Everything's filled with sugar.
"I give in to my cravings. "I'm like, 'Yeah, I can do it. We'll worry about the rest afterwards."
However, the singer-and-actress has been lucky in that she's avoided the perils of morning sickness.
She added in an interview with 'Extra': "Everybody comes up to me and asks me, 'How's the nausea?' and I'm like, 'I don't have any!'"
Meanwhile, the blonde beauty still hasn't found out the gender of her child, and so she expects it to be a "shock when her bundle of joy is eventually born.
Jessica explained: "I feel like it's already going to be a shock. Like, 'Whoa! I just pushed that out!' You know?"