Rosebud,

Let me see if I can answer your questions.

The reason it is recommended you take supplements and multivitamins is the diet itself.

Low carb diets are highly duiretic. You lose a ton of water on them and that is why we recommend drinking 64 oz plus 8 oz for every 25 pounds you want to lose. Keeping the body hydrated makes it function more easily. So because of all the water loss, vitamins and minerals get flushed out faster. So getting them in your food just isn't enough while trying to lose.

Once you get to maintenance then you are eating more and not flushing out so much water.

About sweeteners:
It's all about insulin. Glucose and sucrose are big no no's. If anything go with a sugar free vitamin. If your body is producing insulin, then it is going to store fat. Which makes the diet null and void.

Hope this helps