I am a 55 why.o. Female.
Within 1 hour of eating a meal, all passes through me, prior to which my stomach gets bloated. Any ideas what can be the cause?

Do you still have your gallbladder? If so Do you have IBS? I don't have my gallbladder and I have IBS and have this same problem especially if I wait to long to eat it is really bad. This started for me after I had my daughter and it took awhile for me to discover this but now I just try and eat at about the same time everyday and not wait to long between meals and I also keep Levsin (stomach cramping med) and Imodium (anti-diarrhea med) with me to try and help the problem. But I would say if it is an everyday thing no matter what you do you may want to get it checked out by a doc