PepsiCo quietly announced in December that for an eight-week run beginning April 20, it would make available Pepsi Throwback and Mountain Dew Throwback, "retro" drinks sweetened with real sugar instead of high-fructose corn syrup (HFCS). The company also released a new premium cola, Pepsi Natural, made with all-natural ingredients, including lightly sparkling water, natural sugar, natural caramel and kola-nut extract.

The announcement has been greeted with online cheering from people who have tasted real-sugar versions of soft drinks bottled in places such as Mexico and the UK. Unless they are imported, soft drinks in the United States are sweetened with HFCS. Also cheering was the Sugar Association, which released a letter Monday congratulating the company for its support of the sugar industry in the United States, and subtly encouraging consumers to stockpile "a few cases of each" to send a signal to Pepsi that it needs to extend the marketing period.

Pepsi's experiment should also encourage those who believe HFCS is partly to blame for the obesity epidemic in the US. Experts disagree as to the validity of such claims. Conflicting studies have done little to dissuade people from their beliefs on either side of the sweet divide.

The company says the two drinks actually will be "sweetened with natural sugar, a blend of cane sugar and beet sugar," and it denies that the introduction of the drinks has anything to do with growing public skepticism about HFCS.

Both Pepsi Throwback and Mountain Dew Throwback are available nationwide. Pepsi Natural is available in only 10 regional markets: Chicago, Cleveland, Pittsburgh, Los Angeles, San Diego, San Francisco, Seattle, Portland, Las Vegas and New York.