Sushi consumers should beware of restaurants serving white tuna, or white maguro. The warning follows recent complaints from consumers who have fallen ill after eating the raw fish in Honolulu just this week.

The health department had previously investigated the issue, but is potentially examining it again.

James Tokioka, Kauai representative, noted: "We got calls from people who had gotten sick at a couple of restaurants that they ate the walu at, and we verified it at the emergency room that they went to."

Customers are typically unaware that some restaurants serve escolar or walu but are disguised as white tuna in the menu. A study by Oceana in 2013 revealed that 84% of white tuna that's being sold in the United States is escolar.

What's dangerous about the "very oily, deep water fish with a waxy flesh" is the difficulty in digestion, which can cause diarrhea and stomach pains for consumers.

Honolulu Fishing Agency manager Brook Takenaka says that he would personally never order white tuna due to the fact that "there is no such thing as a white tuna species."

"Anybody that works with this fish knows that if you eat too much of it, then you may have... digestive problems," said Takenaka.

The Department of Health is currently warning individuals who devour escolar to intake no more than six ounces of the seafood in order to avoid illnesses. However, tolerance for the fish is different for every person.

Steve Shibutani, a sushi chef, also cited that he does not even serve the fish. Noting that there is a high demand of it "from mainland visitors to Hawaii."

Shibutani commented, "I guess it tastes good. It's almost an alternative for toro, I guess, real fatty. Even though it's white, it's real rich in the mouth. A lot of people like the richness."

There are no laws that stipulate not to serve escolar. But the Department of Health will be issuing a fine for restaurants and businesses that do not label the fish correctly.

Walu is currently banned in Japan and Italy. Some states in the U.S. have also put in efforts to ban the escolar.