After my recent newsletter about the common myths of Stomach Acid, we have had a few people ask about how to test for low stomach acid. There are actually several options. The Heidelberg Gastric Analysis test is considered one of the most accurate tests. However, it’s fairly expensive (approximately $700).
The Heidelberg test involves swallowing a vitamin-sized capsule containing a pH meter and radio transmitter. You will need to fast overnight (8 hours) before the procedure, and you will drink a solution of water and bicarbonate of soda when you swallow the capsule, which normally stimulates the release of stomach acid. A computer records the readings sent by the capsule to a small medallion placed on your stomach. You will be required to recline for approximately 30-40 minutes.The fluctuations in pH are plotted on a graph, called a gastrogram. Many doctors offices that perform this test allow you the option of having the capsule removed by means of a thin attached string, or just passing it through the digestive tract and eliminating it with a bowel movement.
The Heidelberg test has been used for over 30 years. Well over a million capsules have been used to date. A major area of use is in pharmaceutical research. There have been over 143 published clinical studies with over 73 pertinent studies published since 1977.
The gastro string test is less expensive than the Heidelberg test, but not quite as accurate. The string test involves swallowing a gel capsule containing pH string. You hold one end of the string and swallow the capsule, which makes its way into the stomach where the capsule dissolves and the pH string unfolds. After 10 to 15 minutes, the string is pulled out of the stomach and out the mouth by gently pulling on the end you are holding. The end that was in the stomach is compared to a color key to measure the pH. It should be in the acid range. Neutral pH is a sign of hypochlorhydria. This may also be combined with a baking soda challenge.