As she travels around the world filming her upcoming reality show The Price of Beauty, Jessica Simpson - who underwent criticism for her weight earlier this year - is learning that "beauty starts within," her father Joe tells

"Sheandrsquo;s always scrutinized by the world and [it's great] to watch her go to other countries and see women talk about what is beautiful there," he told Us Friday at a gala in Beverly Hills for the international charity Operation Smile. "We were just in Uganda, and a beauty ambassador [there] knew Jessicaandrsquo;s total story about her weight and blah, blah, blah. [She said] to Jessica that itandrsquo;s about who you are inside, which is the message of our show."

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Asked if he has given his daughter, 29, any advice on how to handle the weight issue, Joe told Us, "I donandrsquo;t have to tell her anything anymore. Sheandrsquo;s wise."

He said he also brushes off any criticism aimed at Jessica or his other daughter Ashlee.

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"The girls are wonderful kids who have so much to offer, and as a father, the greatest frustration in the world is that people are told who they are instead of knowing who they are," he said. "So the hardest thing for me as a parent is to say thatandrsquo;s not who my child is; you donandrsquo;t know the girl because sheandrsquo;s the same girl sheandrsquo;s always been.andnbsp; Sheandrsquo;s with children in Uganda or children in Japan or Thailand -- she has an open heart and loves these people. I think you'll see that on our show. I think it's the greatest show that women can experience because it's all women all around the world talking about beauty and the message is always the same: It starts inside."

What can viewers expect?

Jessica "becomes a Geisha in Japan," Joe told Us. "In Uganda, we sat in a fattening hut because, in Uganda ... fat is beautiful.andnbsp; So the bigger you are, the more beautiful you are. She was with a girl who had been in a hut preparing for her wedding for two months and 25 days on a 5,000 calorie-a-day diet."

See Jessica Simpson's wardrobe malfunction

Next stop: Morocco.

"Itandrsquo;s going to be beautiful," he said.

Jessica agreed, telling Us, "It's going to be amazing ... we're leaving the day after tomorrow I think."