ADIPOSE FATTY-ACIDS AND CANCERS OF THE BREAST, PROSTATE AND COLON - AN ECOLOGICAL STUDY

Animal and ecological studies suggest that linoleic acid intake is rel ated to breast-cancer incidence. Analytical epidemiologic studies, how ever, do not support such findings. The primary objective of our ecolo gical study was to investigate the association between breast-cancer i ncidence and linoleic acid status across European countries. In additi on, other fatty acids and cancer sites were studied. Mean fatty acid c omposition of adipose tissue samples in 11 centres from 8 European cou ntries and Israel served as indicators of exposure of the population. Figures on cancer incidence for the respective or comparable regions w ere obtained from published data. N-6 fatty acids in adipose tissue ra nged from 10.4 in Helsinki to 24.6 g/100 g fatty acids in Jerusalem. N -6 fatty acids were not associated significantly with breast, colon or prostate cancer. Cancers of the breast and colon were associated nega tively with cis-mono-unsaturated fatty acids and positively with trans fatty acids. Despite a large range in intake, we found no evidence of a positive association between n-6 fatty acid status and breast cance r, but associations were observed between other fatty acids and cancer . Differences in linoleic acid intake cannot explain risk differences in breast-cancer incidence between affluent countries, while associati ons of other fatty acids with cancer rates may reflect cultural differ ences. (C) 1997 Wiley-Liss, Inc.