The transition from a standard Western diet filled with sugar and flour to a diet of whole foods, including an abundant variety of vegetables, can initially cause some gas as the body adapts to the increased quantity of fiber. Continued gas is not typical, however, and you may want to work with your GI doctor to explore the reasons for excessive gas, should you be experiencing it. Every digestive system is different, and we have not found universal patterns in this regard. For some people, legumes cause gas—for others, they are fine. For some people, dairy causes gas—for others, dairy products are fine. You will have to experiment to see which foods may be contributing to your excessive gas.