your metabolism will also lower, by burning off lean muscle, if there is absolutely no carbs in your diet. include a bit of carbs, just make a good choice in which kind of carbs. small servings of things like wholegrain, wholewheat bread, rice, etc. the ultimate carb to include is oats. half a cup with water is 150 calories and a goldmine of good nutrition. apparently athletes only eat oats for carbs.
