"90 minutes a day," Jenny said of her Bikram yoga routine.
But it's not just yoga that keeps Jenny in top form.
"That's Bikram yoga and also healthy food," Jenny said of her svelte figure on the cover of Shape.
"You know what though?" Jenny continued. "I don't want people to look at that [cover] and go 'Bitch!' when they see it because there is a lot of airbrushing."
Magazine talk aside, Jenny revealed her beau, Jim Carrey, appreciates her workout routine.
"Jim is absolutely in love with Bikram yoga and he's never tried it, strictly on the fact he loves the way my butt looks, although he would love me, I think, [at] 250lbs," Jenny smiled.
But would she love him? Jim is reportedly gearing up to play Curly alongside Sean Penn and Benicio del Toro in "The Three Stooges," and Jim plans to gain weight for the role.
"He said, 'You know, I'm going to have to gain 40-50 pounds for this role.' And I said, 'Oh my god! I get to be dating Curly!' That is the greatest thing ever."
Jenny is worried though that she may join Jim in his eating routine.
"I hope I don't have sympathy weight because he's going to be eating donuts and I'm going to be going, 'Ooohhh!' Especially during PMS," she said.
While she is playful during interviews, in her crusade over autism issues, Jenny is deadly serious.
Her son, Evan, 6, is autistic. Appearing healthy now, for years he manifested serious symptoms of the disorder.
Jenny claims to have recovered Evan through alternative methods, which she teaches in her third book on the subject, "Healing and Preventing Autism."
"We take the parent step by step with the doctor and how to heal autism," she said of the book. "We have some preventative measures."
For Jenny, prevention lies in safer and fewer vaccines. Convinced they caused Evan's autism, she encourages parents to question and possibly abstain from certain shots.
"I'm not anti-vaccine," she said. "I'm not an idiot. I get that we need them, but I do think people need to wake up and take a look at the schedule.. and why did we triple the amount?"
It's a fact that the number of recommended vaccine shots and the number of autism cases have both increased over the last 20 years. The CDC contends there is no link between the two. Jenny said they still have yet to look at her work.
"History is going to show the truth, just like with tobacco science, you know," she said. "History repeats itself and this is a perfect example."
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