leaky gut and betaine hcl
if you are going to be eating anything. having proper stomach acid to do the job is priority...not enough acid will result in undigested protiens entering the bloodstream as antigens and being attacked by the immune system causing constant stress...many know what this feeling is like. betaine HCL therapy is actually the beginning to healing the leaky gut as undigested proteins are the harsh substances wearing thin the intestinal walls especially gluten. stomach acid will not leak through your gut more than anything else...in fact the goal is for all of the betaine HCL taken to be used in digesting food in the stomach, no more no less. so at the end of that there will be no more acid to create what you call acid/toxicity feelings. i am familiar with these as i went through them, but they are not caused by stomach acid i can assure you. if anything these feelings are caused by a lack of stomach acid to properly digest food and maintain ph balance throughout the gi tract.
healing the gut can be done simultaneously with betaine hcl supplementation. licorish root, marshmallow root teas between meals will help to alleviate inflammation, create protective mucus, and heal the gi tract. l-glutamine and aloe juice with removed bitter leaf will help heal and soothe also. again this is usually taken in between meals on an empty stomach so as not to encourage indigestion and the alkalising of much needed stomach acid. mucin complex can be taken 15 minutes before meals(gastric mucin is a mucus that covers the inside of our digestive organs to prevent acid corrosion, it is an animal derived product)...this is essentially adding mucin just as we are adding betaine hcl.
good luck
hope everything has been illuminated