For the general population, removing gluten isn't necessary. Gluten is found in wheat, barley, rye and any foods that contain these grains (even in super tiny amounts). So unless you have celiac disease, an allergy to any of these grains or a true gluten sensitivity you don't need to avoid these grains. Whether you choose gluten free grains (like corn, rice or millet) or not, whole grains are a healthy choice. In fact, half of your grain choices in a day should be whole grain.
Gluten also doesn't cause weight gain on its own. Inactivity, excessive portions and a poorly balanced diet contribute to this. If you think you might have a gluten sensitivity, I'd suggest speaking to your local health professional first. Many things can contribute to stomach upset besides certain food sensitivities like medications and stress.