Mila Kunis and Ashton Kutcher stopped by Dax Shepherd's Armchair Expert podcast last week to offer up a unique parenting tip from their household: they only bathe their children when they're visibly dirty.

The conversation started when Shepherd remarked during the July 19 episode that he and wife Kristen Bell had stopped putting their own kids through their nightly bath time routine once they got a little older.

"That's how we feel about our children," Kunis agreed.

"Now, here's the thing: If you can see the dirt on them, clean them," Kutcher explained. "Otherwise, there's no point." (Kutcher and Kunis are parents to daughter Wyatt, 7, and son Dimitri, 5.)

Speaking of their own showering habits, both actors admitted they refrain from using soap on their entire bodies every day in order to prevent their bodies' natural oils from being scrubbed away.

"I wash my armpits and my crotch daily, and nothing else ever," Kutcher said. "I got a bar of Lever 2000 that delivers every time. Nothing else."

He continued, "I do have a tendency to throw some water on my face after a workout to get all the salts out," while Kunis added that she washes her face religiously "twice a day."

For her part, the Jupiter Ascending star recognizes that part of her hygiene habits may stem from her childhood.

"I didn't have hot water growing up as a child, so I didn't shower much anyway," she said. "But when I had children, I also didn't wash them every day. I wasn't that parent that bathed my newborns — ever."

Editor's note: An early version of this story erroneously referred to Ashton and Mila's children as their "daughters," though the couple have a son and daughter. We regret the error.

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