Some Starbucks customers are venting that their morning Venti is causing them to run to the bathroom after they drink Oleato coffee beverages infused with extra virgin olive oil.
"Have you tried them?" a Reddit user by the name of "MoodyStarGirl" posted on the social media site on March 16 about the drinks.
She started a thread titled "olive oil drinks" after her store manager did not want the staff to share the unpleasant side effects with their customers, she wrote in her posts.
"I'm wondering how many people are going to have happen to them what a few happened to our team," the person continued.
"Half the team tried it yesterday and a few ended up ... needing to use the restroom, if [you] know what I mean."
She said she was "scared" to sample it because "I already have stomach/bowel problems," she wrote.
The user did not immediately respond to FOX Business's request for comment.
The coffee chain debuted the Oleato beverages in Italy this February. The new drinks have rolled out since in some major cities across the U.S.
Howard Schultz, who recently stepped down as interim chief executive officer of Starbucks, took his first trip to Italy in 1983.
He "discovered the extraordinary relationship that the Italian people have with the Italian coffee bar, and specifically espresso," according to a statement before Oleato’s debut.
"I raced back to the United States with a vision and a passion to bring that to Starbucks."
But last year, while Schultz was traveling in Sicily, he discovered the Mediterranean custom of taking a spoonful of olive oil each day.
Soon his daily ritual included a morning coffee and a spoonful of Partanna extra virgin olive oil.
So he got the idea to put them together, the statement said.
"Now, there's going to be people who say, ‘Olive oil in coffee?" Schultz asked. "But the proof is in the cup."
Starbucks describes the new drink as "coffee meets olive oil."
The company named it after the Latin word for olive and an Italian word that give homage to the process of infusing the olive oil with coffee, a Starbucks statement said.
"You can find them in stores in Seattle & Los Angeles, Starbucks Reserve® Roasteries in Chicago, Seattle & New York, Starbucks Reserve® Empire State Building® store, the Starbucks Reserve® locations in SoDo Seattle & Greenwich Lane in NYC, and Seattle’s Pike Place market," Starbucks shared on March 27 in one of its tweets about the new drink.
But not all customers are sharing the brand's enthusiasm for the beverage.
"Caffeine is a stimulant for your bowels and oil a relaxant," one Reddit user lamented. "So, yeah, wonderful idea by Starbucks."
Another user was even more blunt: "You’ll run to it … and from it."
TikTok users were equally critical.
"Is this a joke? Is that not a cup of bacon grease," one questioned.
Another went viral after posting her order: an iced latte that is "like an oil spill on your iced coffee."
But other customers said they've been enjoying the new drink line.
"Got a sample of the iced Oleato this morning. Very flavorful. Might be my new favorite," someone tweeted on March 27.
"Starbucks, the new Oleato drink is so damn delicious! Love it!" another wrote on Twitter.
Starbucks did not respond immediately to a request for comment from FOX Business.
"Coffee contains caffeine, which is a stimulant," Roxana Ehsani, registered dietitian nutritionist and board certified sports dietitian, located in Miami, Florida, told FOX Business.
"Not only does coffee wake you up, but it also wakes up your colon, too."
Coffee can work as a natural laxative that contains natural acids, "which stimulate muscle contractions [to] get your bowels moving," she explained.
It also stimulates another hormone, called cholecystokinin, in the gut as well, which can cause some people to run to the bathroom, she noted.
She points to previous research showing olive oil was as effective as mineral oil in the treatment of constipation in patients with severe kidney disease who were on dialysis.
Olive oil softens the stool, which makes the stool pass easier, so people don’t have to strain as much when they go to the bathroom, she explained.
"So together coffee and olive oil, seems to be causing a lot of people to run to the bathroom, which is likely due to both of their laxative properties," Ehsani said.