well... how does your tummy feel when you don't suck it in!?
Also, I seriously doubt most peoples abs are strong enough to impinge on their intestines.

Not a great idea, because you are not allowing your diaphragm to descend fully & so cannot take a full, natural breath.

This can lead to low level anxiety and I wouldn't be surprised if it is affecting your digestion.

Watch babies breathe. Their bellies move up & down, not their chests.

This is a really bad habit, especially for women. Often we have been taught to hold in our bellies & tuck in our pelvis. Fine for a short military display or abdominal exercise (like planks), but really damaging as a long-term habit, since it can lead to pelvic floor prolapse in women.

Here's a good book that may be helpful (written by one of my teachers):

http://www.amazon.com/Conscious-Breathing-Breathwork-Release-Personal/dp/0553374435

I actually think yes. I know doing the same thing for me actually left my core rather weak and gave me a shoulder problem (for the shoulder trying to take the stress the core was not absorbing), so it doesn't seem far fetched to me that it could be contributing. I would work on proper diaphragmatic breathing and see if it helps.

I don't clearly understand your post. Are you saying that you have a bit of a beer gut, and so you suck it in all the time, but you are also having internal abdominal pain, and suspect that the pain may be caused by constantly keeping your abdominal muscles under tension? I doubt sucking in your gut is the cause of your pain.

I'd be more worried about these:

• years of drinking
• abdominal buldge
• persistent abdominal pain

You should really get to a doctor and have some tests done. You could have liver issues, a tumor, or some other scary funk going on.

It definitely impacts on my IBS when I wear clothes that are too tight - even if they're soft clothes but I hold my belly in to fit them. Even if I'm not aware of being tense, I get a flare that takes a couple of days to resolve.