Unfortunately it is unlikely that removing gluten will decrease your waistline. However reducing gluten can have an extremely positive effect on the body as breaking this can be an issue for some people.
If you want a smaller belly I would suggest looking at your diet and the amount of exercise you take.
If you are not up for that I would recommend purchasing a juicer with a juicing plan. Then simply juice to your hearts content for as long as you like. You can expect to shed at least 3-5 lbs in your first few days & you would be amazed how tasty the juices are.
As a little side note: Do not over look a juice because you do not like the taste of an ingredient. I can not stand celery but I do not even notice it once it has been juiced.
Good luck with the belly, lets hope it does not get you!