Using Cal Civ Code § 1694.7 as a guide, needs to create a Weight Loss Contract. Note the California definition of what is a Weight Loss Contract.

The phrase "weight loss contract," as used in Civ. Code § 1694.5 et seq. means a contract with any weight loss program or center that offers instruction, counseling, supervision, or assistance in weight reduction, body shaping, diet, and eating habits, by persons who are not licensed health care professionals; the use of facilities of a weight loss center for any such purposes; or membership in any group, club, association, or organization formed for any such purposes. "Weight loss contract" also includes a contract with any weight loss program or center that provides prepackaged or premeasured "diet foods" [Civ. Code § 1694.5(a)].