Why do I feel a lump in my stomach when sitting up?

When you sit up and feel a lump in your stomach, it could be because certain structures shift or become more obvious when you change position. One possible explanation is a hernia, where part of your internal tissue pushes through a weak spot in your abdominal wall. Sometimes, benign growths such as lipomas (fatty tumors) or cysts can also present as a lump that is more noticeable when your abdominal muscles are engaged. In rare cases, more unusual conditions like a gastric volvulus, where your stomach twists on itself, might cause symptoms including a palpable mass, although this is less common and associated with pain and vomiting. Since there are several possible reasons for this sensation, it's important to have it evaluated by a healthcare provider. You can start by taking a free symptom checker to help identify potential causes before your appointment. They can perform a physical examination and may order imaging tests to accurately determine what is causing the lump and recommend the proper treatment if needed.