Low-carb drink, option 1

Pictured is my fave low-carb (or rather no-carb) drink: San Pellegrino sparkling water. Any water is an excellent choice and you should drink at least 1,5 litres per day. In very hot weather, you should drink double that amount.

However, make sure you get enought salt, since a low-carb diet flushes out salts from your body in the beginning, and it is this lack of salt that can cause a feeling of light-headedness in the beginning stages.