“…We excluded 18 articles [25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42] for the following reasons: description of only study protocol or rationale (n = 4) [25,26,27,28], precancerous lesions or nonskin cancer as outcome measures (n = 12) [29,30,31,32,33,34,35,36,37,38,39,40], and use of supplements not relevant to the current study subject (n = 2) [41,42]. …”