This study will examine the effect of fasting on lymphangioleiomyomas abdominal tumors formed from enlarged lymph nodes containing lymphatic fluid. Previous studies have determined that these tumors increase in size in the evening, but this result could stem from the fact that previous study participants were tested after eating lunch. The purpose of the study is to help researchers understand the factors that produce changes in size of lymphangioleiomyomas, as well as to improve the ability of medical professionals to diagnose lymphangioleiomyomas and avoid confusing these tumors with other malignant tumors.