Research from several sources provides strong evidence that vegetables, fru
its, and whole grains, dietary fibre, certain micronutrients. some fatty ac
ids and physical activity protect against some cancers. In contrast, other
factors, such as obesity, alcohol, some fatty acids and food preparation me
thods may increase risks. Unravelling the multitude of plausible mechanisms
for the effects of dietary factors on cancer risk will likely necessitate
that nutrition research moves beyond traditional epidemiological and metabo
lic studies. Nutritional sciences must build on recent advances in molecula
r biology and genetics to move the discipline from being largely 'observati
onal' to focusing on 'cause and effect'. Such basic research is fundamental
to cancer prevention strategies that incorporate effective dietary interve
ntions for target populations. Crown Copyright (C) 2001 Published by Elsevi
er Science Ltd. hll rights reserved.