1. Emergen-C drink packets are a new favorite. Some kinds have about the same stuff that's in a multivitamin. 25-35 calories per packet, depending on the type. It makes a fizzy flavored drink - and no upset tummy like taking a vitamin on an empty stomach.
2. True Lemon, or Orange, or Lime packets are good too. Bunch of vitamin C, no calories or carbs, no sweeteners or sodium. Makes getting down the daily water a bit easier.
3. Comparison: Peanut Butter and Jelly Sandwich. As per serving sizes, a PB&J made with 70 cal/ slice bread, 190 cal/ 2 tablespoons PB, and 50 cal / tablespoon jam = 380 calories
Whereas a PB&J made with 70 cal/ slice bread, 1 tablespoon PB, and 10 cal/ 1 tablespoon Sugar Free jam = 245 calories
[For a even bigger stretch, heat or toast the bread first. Then smear on 1 teaspoon of peanut butter and 1 tablespoon of sugar free jam. (PB smears easier and thinner when hot, so less can be used). This would equal 182 or less calories.]
But my basic point is that you can take a 380 calorie sandwich and turn it into 245 calories without anyone noticing that you're eating a hundred less. [And the heated bread sandwich - could eat two of those and still not equal the calories of a normally prepared PB&J]