James, what do you suppose causes low gastric acid over time?
I think the primary reason is decreased methylation. Methylation is required for the production of stomach acid. Although as stomach acid decreases this also reduces the absorption of the nutrients needed to produce stomach acid. And as stomach acid decreases people tend to get heartburn and take antacids and acid blockers, which in turn further leads to the nutrient deficiencies that interfere with stomach acid formation.