It means that the stomach is very acidic.
The stomach has a low pH (is acidic) because of the Hydrochloric Acid (HCL)
Low pH is needed to start the denaturation and digestion of proteins, which occurs in the stomach.
By increase I believe you mean the pH gets more acidic. The stomach is full of acid that is very low on the pH scale, and the lower in the pH scale, the more acidic Hydrogen bonds become. So, basically the more acidic the pH in the stomach, the better the food can be broken down (decomposed).
The stomach (part of the digestive system) has a low pH (acidic), which kills pathogens.
Many bacteria doesn't support a very low pH.
The lower a pH level is, the more acidic it is. The acid in your stomach, hydrochloric, is very acidic, and can even burn through some items.
Bactericidal
HCl
6.5 pH is too low pH for the blood. It is dangerous. You have got acidosis. The physician will take prompt action. The same pH in the stomach is too high. It is not dangerous. But it may hamper proper digestion of the food.
Low: acidic.
pH 2This is because pepsin, the primary digestive enzyme found within the stomach, functions optimally at a low pH.
Stomach acid - hydrochloric acid - has a pH of between 1 and 2. This makes the stomach very acidic.