I'm not sure but I think its different if the caffeine is added. And what about this
"Dew Fuel (2002–2007) — A caffeinated version of Mountain Dew offered in Canada.[23] Mountain Dew is not caffeinated in Canada due to Health Canada regulations[24] that only allow caffeine in 'dark-coloured' varieties of soft drinks such as cola and root beer. The reason Dew Fuel is allowed to bypass Health Canada regulations and be sold is due to the fact that it is marketed as a natural health product and not as a soft drink. It mainly replaced Canada's (Caffeine-Free) Mountain Dew on store shelves, although many places still sold both drinks. Dew Fuel was originally called “Mountain Dew Energy” until given its present name in 2006. In early 2007, Pepsi-QTG Canada cited that Dew Fuel is out of production.