(General Mills)

Americans are eating less cereal, but executives at General Mills are hoping they’ve found a way to revive sales: By offering customers a chance to win one of 10,000 boxes filled with nothing but Lucky Charms marshmallows.

On its website, General Mills calls marshmallow-only Lucky Charms “the unicorn of the cereal world — fantasized about, but never seen.” In reality, they come with more sugar per serving than a Snickers bar or Twinkie.

It’s a change in direction for the maker of Cheerios, Trix and Wheaties, which two years ago announced it would remove artificial flavors and colors from Lucky Charms marshmallows by 2017. That effort has since stalled — company scientists have yet to find natural substitutes that won’t affect flavor — but Mike Siemienas, a Lucky Charms spokesman, says work is ongoing.

“It’s still our biggest challenge,” Siemienas said. “We’ll let you know once we’ve found a solution.”

In the meantime, customers can try their hand at winning a box filled with hundreds of marshmallows. Each 6-ounce serving comes with 110 calories and 22 grams of sugar. (Regular Lucky Charms, by comparison, have the same number of calories but less than half the sugar.)

“We brought it back because it’s what our fans were asking for,” Siemienas said. “We’re constantly getting calls, emails, tweets, you name it, from people saying ‘When are you going to put out a marshmallow-only box?’ They’re obviously obsessed.”

The made-for-social-media campaign is the latest to capitalize on the gimmicky and, arguably, gross, according to branding experts. (Other examples: Starbucks’ Unicorn Frappuccino, Jack in the Box’s bacon milkshake and Burger King’s burger-meets-burrito creation, Whopperito.)

“The strategy is always the same: Generating social media interest by creating something that’s highly shareable just because it’s outrageous,” said Kelly O’Keefe, who teaches creative brand management at Virginia Commonwealth University. “Companies don’t consider that a lot of those shares come from people saying ‘this is so gross,’ or ‘this is so weird,’ and that ends up undermining the credibility of the brand.”

General Mills, after all, is embracing the unhealthy with its box o’ sugar bomb — at least temporarily.

The last time General Mills ran a similar promotion, back in 2015, it offered just 10 marshmallow-filled boxes. The winners were chosen from a group of customers who posted photos on social media of themselves pretending to hold boxes of Lucky Charms. The contest lasted five days.

This time around, the promotion will span eight months. And the company and is requiring participants to purchase its cereal. Each specially marked box of Lucky Charms will come with a code in the inside panel. Customers can type in those codes online to see if they’ve won.

“We know people were disappointed when we did only 10,” Siemienas said. “Now their dreams of having a box full of Lucky Charms marshmallows can come true.”

Nationally, cereal sales have been slipping for years — falling about 9 percent between 2012 and 2015 —  as Americans buy more eggs, oatmeal and Greek yogurt. And, research has shown, millennials are less likely to pour themselves a bowl of cereal than their older counterparts because they find it “inconvenient.”

At General Mills — which oversees a number of other iconic food brands including Bisquick, Yoplait and Hamburger Helper — sales slipped 5 percent to $3.79 billion in the most recent quarter.

In recent years, the food giant has begun putting a health-conscious spin on its cereals. Cheerios and many types of Chex, for example, are now marketed as gluten-free. Last year, it added three organic cereals to its Annie’s line, and introduced berry-flavored Tiny Toasts, its first new cereal brand in 15 years. And Lucky Charms — which counts sugar and corn syrup among its four most prominent ingredients — is promoted on the company’s site as being “made with whole grain, fortified with 12 vitamins and minerals, and a good source of calcium.” Its customer base, it said in 2013, is 40 percent adults.

Siemienas says the company isn’t planning on offering marshmallow-only Lucky Charms long term.

“That’s not in our plans,” said Siemienas, whose breakfast of choice alternates between Lucky Charms and Honey Nut Cheerios. “The oat pieces are still very important as well.”

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