To propose a health food or a drug, which comprises an iodine compound as a substitute for organic iodine and can exert a similar effect as organic iodine. To propose a method for producing a liquid to be used as a starting material for the aforesaid health food or drug. A health food and a drug each containing hydrogen iodide as the active ingredient. A method for producing a hydrogen iodide-containing solution, which comprises: an alkaline ion water preparation step for preparing alkaline ion water containing hydrogen peroxide a sodium hydroxide production step for adding sodium to the alkaline ion water and thus producing sodium hydroxide and a hydrogen iodide production step for, after the sodium hydroxide production step, adding iodine to the alkaline ion water and thus producing hydrogen iodide.
