Thanks for consulting at my virtual clinic. I have carefully worked through your case, and I can realize your health worries. Being your physician, I assure you not to worry as I will take care all of your medical concerns.   Changed bowel habits are somewhat serious in that it may be start of some serious gastrointestinal tract disease. You need to consult a Gastroentrologist and get your complete evaluation done in-person over there. He will run a battery of blood work and a Colonoscopy which is very necessary to rule out any disease of the gut. Gastrocolic reflex is rather a normal reflex in which there is a need for evacuation after stomach is hit by food and is filled up properly. But there is no fecal urgency and no discomfort or pain is seen in there normally. So you have something to be ruled out. Start taking Citrucel dietary fiber supplement for forming a bulk of stools normally. Take plenty of water and a vegetable diet with salads and fruits added too. Hope I answered all of your health concerns . If you have further questions in future, feel free to contact me anytime & I will get back to you in no time. Please give a positive feedback. Have a wonderful time ahead.   Best Regards! DR. MUHAMMAD M. HANIF USA