The consumption of lean and fatty fish, different dietary patterns, and the risk of cancers of various sites

Abstract

The present work includes women from three cohorts: the Norwegian Women and Cancer (NOWAC) study, the European Prospective Investigation into Cancer and Nutrition (EPIC) study, and a sub-cohort from the NOWAC study termed the Norwegian EPIC cohort (NEPIC). <br>Despite large differences in nutritional values in lean and fatty fish most studies on fish consumption and cancer do not diverse between these two types of fish. In the present work consumption of lean and fatty fish has been examined in association with breast cancer in the EPIC study, and in association with colon cancer in the NOWAC study. <br>Looking at dietary patterns is a relatively new approach in nutrition epidemiology, and may give a better understanding of the relationship between diet and health. In this work, dietary patterns were identified from the NEPIC cohort, using a combination of factor and cluster analyses. The patterns were further investigated in order to reveal any relationship with cancer of various sites. Total cancer, breast cancer, and gastrointestinal cancers were examined. <br>There were no clear association with fish consumption and breast cancer in the EPIC study. Likewise, there were no association between fish consumption and colon cancer risk in the NOWAC study. However, when dividing lean fish into fried and poached fish, we found a statistical significant increased risk of colon cancer with high intake of poached fish. <br>Six different dietary patterns were identified in the NEPIC cohort. Overall, none of the dietary patterns identified was associated with cancer risk. There was, however, a somewhat higher risk of total cancer and breast cancer for women with a westernised pattern, and for total cancer for women with an alcohol pattern for some of the stratified analysis.

Det er brukt data frå tre ulike kohortar i dette arbeidet: den norske Kvinner og kreft studien (NOWAC), The European Prospective Investigation into Cancer and Nutrition (EPIC) og ein delstudie frå Kvinner og kreftstudien kalla den norske EPIC kohorten (NEPIC). <br>Trass i at det er stor forskjell på næringsverdien i mager og feit fisk er det få studiar som har skilt mellom dei to fisketypane. I dette arbeidet blei det undersøkt om inntak av mager og feit fisk har nokon samanheng med brystkreft i EPIC studien og med tjukktarmkreft i NOWAC studien. <br>Det å undersøkje kosthaldsmønster er ei relativt ny tilnærming innan ernæringsepidemiologi og kan vere ei hjelp til å betre forstå samanhangen mellom kosthald og helse. I dette arbeidet blei det brukt ein kombinasjon av to analysemetodar, faktor- og klyngeanalyse, for å finne kosthaldsmønster i NEPIC kohorten. Deretter blei kosthaldsmønstra undersøkt for ein mogleg samanhang med ulike krefttypar. Dei ulike krefttypane som det blei undersøkt for var total kreft, brystkreft, og mage- og tarmkreft. <br>Det var ingen klar samanhang mellom inntak av fisk og brystkreft i EPIC studien. Det var heller ingen klar samanhang mellom fiskeinntak og tjukktarmkreft i NOWAC studien. Når mager fisk blei delt ytterlegare inn i kokt og steikt fisk såg ein likevel statistisk signifikant auka risiko for tjukktarmkreft ved høgt inntak av kokt mager fisk. <br>Seks ulike kosthaldsmønster blei avdekka i NEPIC kohorten. Samla sett var det ingen samanhang mellom nokon av kosthaldsmønstra og risiko for kreft. I stratifiserte analysar var der likevel ein noko høgare risiko for totalkreft og brystkreft for kvinner med vestleg kosthaldsmønster, og for totalkreft for kvinner med alkoholrelatert mønster.