My food whizzes through my system too, within 4 hours I am on the loo. Mine is caused by food intolerances . When I have the foods under 'control' its only for a few days at a time. Because usually I have discovered yet another food that I have been eating regularly, without problem, suddenly, it causes a problem, and this is happening almost weekly. In between loose stools ( it takes me 4 days to get over a newly discovered intolerance), then I get constipated. Everyone in my house cheers if I do a normal poop, its that rare!
Pancreatic enzymes did nothing for me. I took both the ones I bought and the ones my Dr prescribed which were 10 times stronger. So saying that, they may work for you, each to their own discovery.
Next week I am off to the BIG hospital for much deeper tests on my liver and digestion system to find out why I am 'shitting' myself almost to death. I suspect a liver issue, because often it feels like its on fire. I know I have a benign liver tumour already. The annoying part is, I have never done alcohol to excess and all my life I have eaten healthily, I have never liked junk foods.
Try doing some research on foods that are known to cause loose stools. But check lots of different sites because I have yet to find one that comprehensively lists every food that are known to cause digestive issues.