I don’t want to cause alarm in the people who have to take Omeprazole because everyone is different.
I was Prescribed Omeprazole which I now know lowers stomach acid (which in my case as I had low stomach acid to start with and so was extremely bad). It caused me not being able to metabolise the iron in my diet and becoming severely anaemic. That meant that the red blood cells were unable to pick up sufficient oxygen and transport it to the cells which were crying out for it and so the heart was pumping harder and faster to try to help. This resulted in the heart becoming permanently thick therefore stiff. Hence my heart problems.
Apparently in some people their stomach acid becomes less as they age. The tendency must be hereditary because my maternal grandmother had to take stomach acid pills as did my cousin. I did not know this at the time. I just blithely swallowed what the doc prescribed without question. Never again!
You can do a rough and ready test for stomach acid by swallowing a certain amount of bicarb in water first thing in the morning and see how long it takes you to burp. You can see how to do the test by googling it.