"The American Medical Association has confirmed that HFCS is no more likely to contribute to obesity than table sugar or other full-calorie sweeteners," the post continued. "Please be assured that Coca-Cola brand soft drinks do not contain any harmful substances."

Donald Trump said Coca-Cola had agreed to sweeten its signature soft drink with cane sugar in the US, in what could represent a major shift from its decades-long use of high fructose corn syrup.

Archer-Daniels-Midland, a leading processor and trader of agricultural commodities like corn, saw its stock tumble 5% in after market trading.