EFFECT OF DIETARY FISH-OIL ON FECAL BILE-ACID AND NEUTRAL STEROL EXCRETION IN HEALTHY-VOLUNTEERS

Diet-induced increases in fecal excretion of secondary bile acids (deo xy-and lithocholic acid) and certain neutral sterols (4-cholesten-3-on e and 5a-cholestan-3-one) play a role in colon cancer development, whe reas dietary fish oil (FO) has been implicated as a protective agent. In the present study the effects of FO and corn oil (GO) on these feca l parameters were investigated in 12 healthy volunteers consuming a lo w fat (30% of energy) controlled basal diet. After 4 weeks of FO suppl ementation (4.4 g omega-3 fatty acids/day), daily excretion of lithoch olic acid showed a trend to lower values compared to CO consumption (p =0.2), whereas other bile acids were not different during both study p eriods. Daily excretion of the putative colon carcinogen 4-cholesten-3 -one was significantly lower in the FO compared to the CO period. This may be another biochemical mechanism by which FO exerts its protectiv e effect on colon cancer development.