Guar gum and xantham gum are all fiber and so the carbs are practically zero. They give a finish that is shiny and translucent like corn starch does. Add some heavy cream for a creamy gravy-like appearance.

Guar gum thickens both hot and cold liquids.

A little goes a LONG way so start with a very small amount - say, 1/2 tsp for a couple of cups of liquid - then you can add more.