no matter what or how much
i eat runs through me within 45 minutes and sometimes faster. I am afraid to eat this has been going on for 4 months
You may want to read about Irritable bowel syndrome to see if the symptoms sound like what you are having. You may also want to track what you are eating to see if it's worse with some foods than with others; it's possible that you have some food sensitivities/allergies going on.
Four months is really a long time for this. It's important to get to your doctor for a thorough evaluation. If you can do a food/symptom log while waiting for your appointment it will help your doctor get a full picture of what is going on.