Many people have argued for both the low fat diet and the low carb diet. I've done both and they both reduce symptoms on their own.
What I've noticed though is that symptoms flare up only when I eat Fats and Carbs together in combination.
I went on a low fat/high carb diet for 3 weeks and ate lots of bread, fruits, rice.... and my symptoms reduced. It's only when I re-introduced fat that I had a flare up.
My conclusion is that both Low fat and Low carb diets will do the job as long as you don't mix fats and carbs.