The proton pump inhibitors will also affect:
zinc
iron
B12
folate
calcium (leads to osteoporosis
magnesium (this is sometimes very severe)
some trace minerals

On PPIs, you will also not digest or break up protein properly, and hence may be low in amino acids. You can make whey protein shakes and perhaps overcome this. Low protein will affect the formation of carrier proteins in the blood that transport hormones and other things. So you might show evidence of poor hormonal actions. Poor protein digestion provides substrates for
bacteria in the bowel, to flourish and ferment the protein into gas which rises and causes all sorts of reflux.

Sometimes stomach problems are really slow gall bladder symptoms. This causes gas and pain. 1000mg of taurine daily can help this... it improves bile flow so things don't get stuck.

Your B12 should be at 400pg/ml. Anything lower is not "normal" but labs still use the old outdated ranges.

Magnesium levels in the mid range are not predictive of anything.
This test is only really useful for very very low or very very high situations. (either can be life threatening). But all the rest of that range does not illustrate what is going on in your body.
You can read more here:
http://www.slowmag.com/
This site gives food choices to maintain healthy magnesium metabolism in the body. Up to 70% of people in the US are low in magnesium (intake 1/2 or less of the RDA).
Taking a drug to impair magnesium absorption, you may have to
use a topical form. There is a new nice one...Morton Epsom Lotion. This is available at WalMart, Walgreen's, and Amazon.
It really helps.

This is my mag thread :
http://neurotalk.psychcentral.com/thread1138.html