I think a confounding variable for this is the caloric load. Drink 5 cans of coke and thats what, 1000 calories at least? You feel it impact the rest of your fo

I think a confounding variable for this is the caloric load. Drink 5 cans of coke and thats what, 1000 calories at least? You feel it impact the rest of your food intake. Meanwhile, diet drinks are zero calorie. Many older people I know who consume diet soda do it to the exclusion of actual water, which they can do since its zero calories and doesn’t impact their appetite for their other meals. For what its worth all of them are overweight.