Les I don't see why you couldn't - reading the back of the Pepsi max I've got it has no carbs, no calories. It's as harmless as water, as far as I can tell. I mean, exante is full of artificial sweeteners, so they can't be a bad thing. I'd say have it in moderation. I used to be a self confessed queen of pop (ha!) and drank about 1-2l of Pepsi max a day, but since I've been on exante i think I've had about 2-3 cans of it in three weeks. I just make sure to buy 0% sugar squash! It feels like it's costing me a fortune I'm going through so much of it, but it's probably working out a lot cheaper than my Pepsi habit really!