a result，claims that eating a diet consisting entirely of organically grown foods prevents or cures disease or provides other benefits to health have become widely publicized 宣传 and form the basis 基础for folklore.民间
(同位语从句claims that…)
结果，那些认为只食用绿色食品就能防治疾病或增进健康的观点广为人知，并成为一些民间说法的基础。
分句 1： that eating a diet consisting entirely of organically grown foods prevents or cures disease or provides other benefits to health
分句2：claims have become widely publicized and form the basis for folklore
分句2嵌套分句1，分句1作为分句2主语的同位语从句嵌套在分句2中。因此本句的主句是 claims have become widely publicized and form the basis for folklore. 那些观点广为人知，并成为一些民间说法的基础。同位语从句是 that eating a diet consisting entirely of organically grown foods prevents or cures disease or provides other benefits to health：只食用绿色食品就能防治疾病或增进健康