The Beet Test

Eat beets. If they turn your urine pink/red, then you have low stomach acid. Stomach acid is a very important first step in digestion. Without enough, you can't absorb B12, and you have trouble absorbing zinc as well as several other nutrients. If you don't have adequate stomach acid, proteins aren't broken down properly, and so they can cause trouble in the small intestine and/or get absorbed whole into the bloodstream.

Gluten and casein are famous for being addictive because they form opiod-like substances. Stomach acid is necessary to prevent them from becoming opiods.

Histamine helps trigger the release of stomach acid. Histamine is found in several foods, especially ferments, so pile on another reason to eat ferments with every meal. Adequate zinc is also necessary to produce stomach acid (remember what's not absorbed well without it?).

Source: HealThyself