The online company that sells the product claims Hoodia contains a molecule called P-57, which is said to reduce appetite.
One user reported losing 25 pounds in just three months.
Meanwhile, some experts remain suspicious of the new Ice Cube Diet, because two pharmaceutical companies backed away from it.
"Pfizer actually tried to develop this into a drug and stopped its clinical trials without really an explanation, and then Unilever who makes Slim Fast was going to make a drink with Hoodia and they also discontinued the development of this drink," said dietician Alicia Puma.
The diet costs around a $1.50 a day, and the ice cubes reportedly tastes like margaritas.