Iowa Code § 190.11: Artificial sweetening — labeling.

Where any approved artificial sweetening product such as saccharin or sulfamate is used by any person in the manufacture or sale of any article of food intended for human consumption, the container in which any such food or beverage is sold or offered for sale to the public shall be clearly, legibly and noticeably labeled with the name of the sweetening product used. The portion of the store, display counter, shelving, or other place where such food or beverage is displayed or offered for sale, shall be clearly and plainly identified by an appropriate sign reading:

FOR DIETARY PURPOSES.