Chronic diarrhea is not typically expected 20 years after gastric bypass surgery, but it can occur in some individuals due to various reasons. While gastric bypass is an effective procedure for weight loss, it alters the digestive system significantly, and some long-term effects may develop over time. One possible cause of chronic diarrhea could be dumping syndrome, a condition where food, especially sugary or fatty foods, moves too quickly from the stomach to the small intestine. Although this is more common in the early years after surgery, some individuals may experience it long-term if their diet includes foods that trigger this response. Another potential factor is bacterial overgrowth in the small intestine, which can sometimes develop due to changes in the digestive tract after bypass surgery. This can lead to diarrhea, bloating, and discomfort. Additionally, malabsorption of nutrients, particularly fats, might result in loose stools, especially if dietary adjustments or supplements are not managed well. Food intolerances or sensitivity to certain ingredients like lactose can also contribute to chronic diarrhea. Over time, your digestive system may respond differently to foods you previously tolerated. While chronic diarrhea is not a common or expected outcome two decades after gastric bypass surgery, it is not unheard of and should be evaluated to ensure your digestive health is optimized.