Betaine HCl is the most common hydrochloric acid-containing supplement. Normally it comes in tablets or capsules measured in grains or milligrams. Only people who have reduced levels of stomach acid (“hypochlorhydria”) should take betaine HCl; this condition can be diagnosed by a doctor. When appropriate, some doctors recommend taking one or more tablets or capsules, each 5–10 grains (325–650 mg), with a meal that contains protein. Occasionally, betaine (trimethylglycine) is recommended to reduce blood levels of a substance called homocysteine, which is associated with heart disease. This form of betaine is different from betaine HCl.
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