Hi
Welcome to the MedHelp forum!
Greasy food can cause indigestion and diarrhea if you have IBS, liver, gallbladder or pancreatic problems. Hence get this assessed by your PCP followed by a referral to a gastroenterologist.
Hope this helps. Please let me know if there is any thing else and do keep me posted. Take care!
Do you have your gallbladder still? Grease food caused me to have diarrhea and vomiting. After I got it out it stopped. Hope you feel better soon!