CANCER PREVENTION STUDIES - PAST, PRESENT, AND FUTURE-DIRECTIONS

In spite of extensive research on vitamins and diet, a consistent bene ficial role of vitamin supplements, together with diet modification in human cancer prevention, has not been demonstrated. Published results of human intervention trials with vitamin supplements have been contr adictory. This review critically, but briefly, evaluates (a) current c oncepts of human carcinogenesis, (b) effects of vitamins on biochemica l parameters that are pertinent to cancer prevention, and (c) whether past or current protocols for intervention trials among high-risk popu lations adopt specific scientific rationales that are based on laborat ory and human epidemiology studies. In addition, we propose a novel ex perimental design for intervention trials among high-risk human popula tions that is based on sound scientific principles derived from labora tory and human epidemiologic data on vitamins, diet, lifestyle, and ca ncer prevention. Such trials would answer a fundamental public health issue of today: Does supplementation with multiple vitamins, together with diet and Lifestyle modifications, reduce the risk of cancer? (C)E lsevier Science Inc. 1998.