Julia Roberts is on a mission to lose weight, after playing a slightly dowdy mom in Ben Is Back. But she’s not dieting solo, RadarOnline.com has learned exclusively. She’s making the whole family follow her detox diet too — and hubby Danny Moder is fed up!

“She’s demanding they eat only ‘colorful’ fruits and veggies, raw nuts and seeds,” an insider told Radar. “Tofu and tempeh are okay but no meat, no dairy, no sugar, no processed stuff.”

The battle of the bulge comes as the pair continue to digest some troubles in their marriage, reveals the informant, such as Moder’s alleged jealousy over Robert’s reconnection with former Pretty Woman co-star Richard Gere.

is packing on the pounds, says the source, with some estimates of her weigh gain as much as by 50 pounds.

Moder, who has been married to the Erin Brockovich star for the past 14 years, doesn’t think she even needs to diet – she looks great to him – but she’s hell bent on flushing out all the toxins.

“When she’s detoxing, she’s basically a crazed hungry person and irritable,” the source revealed.

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As for Moder, he’s starting to miss the comforts of fast food.

“Danny is pretty healthy, but he likes the occasional street taco,” the source said. ”He’s tried to sneak out for a snack but Julia actually smells his breath when he gets back. So he’s hungry all the time.”

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