Calorie Police Patrol Supermarket Isles

PHOTO: Cameras capture reactions when a mom is harassed by other food shoppers. PlayABC News
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From first lady Michele Obama to the hosts of weight-loss-themed TV shows, America is turning up the volume on an anti-obesity message centered on eating right. But is it acceptable for a fellow shopper to berate a parent buying junk food?

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John Quinones Appears on Jimmy Kimmel Show

What would you do if you heard criticisms hurled across the grocery aisles?

The hidden cameras of ABC News' "What Would You Do?" captured the scene inside an IGA supermarket in Fort Salonga, N.Y. Pushing a cart filled with junk food, actors played the role of an overweight mother, Melia, and her daughter, Kate. Two actors portrayed shoppers who harassed Melia about her food choices.

The first actor who spoke out as an outraged member of the food police was Tracy.

"You are what you eat," she blurted at the start of an increasingly aggressive harangue. "You're teaching bad habits. I have to take care of you later in life when you have diabetes -- that's all I'm saying."

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Then she took the harassment a step further and tried to push even hotter emotional buttons.

"You're in control, and for you to treat her like this, you don't really love her," Tracy said.

Outraged, Melia, fought back.

"I love her," she said. "You cannot stand there and tell me that I don't love my daughter because of what I'm feeding her."

A crowd overheard the unsolicited comments and, while several people walked by, one young couple stopped. Christine and Jim told Tracy, "Why don't you mind your own business, ya know?"

Sheer Harassment or Does She Have a Point?

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After Melia and Kate walked away, leaving Tracy alone with the couple, their tone changed. They appeared to agree with the critic's message.

"Did you see how much sugar?" asked Tracy.

"Yes, I know, I know. It's like, horrible. It's a nightmare," Christine replied.

Jim added, "You just care."

Later, ABC's John Quinones, host of "What Would You Do?" spoke with Christine and Jim at the check-out counter. He asked them for feedback on the staged confrontation they witnessed.

"[Tracy] had a point, you know?" Christine said. "It's, like, none of her business. But then, in a way, it's like she's trying to save this person's life. ... It was positive but negative at the same time."

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Back in the shopping aisles, Tracy began haranguing Melia and Kate again.

"Everybody in here has healthy stuff in their basket but you," she said. "You don't have one fruit!"

When Melia began to defend herself, a shopper named Patricia was loud and clear in her support.

"This is her life and her family and none of your business," Patricia told Tracy. "This is inappropriate in a public place, and you should keep your mouth shut. You have no right to humiliate them."

Afterward, Patricia, a school librarian, spoke with Quinones about her reaction. She told ABC News, "I would never embarrass someone, because I know what it feels like to be embarrassed."

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What will happen if the one hurling the insults is a man?

Watch the scenario unfold Friday, 9 p.m. on "What Would You Do?"