Olive oil, diet and colorectal cancer: an ecological study and a hypothesis.

Unit of Health-Care Epidemiology, Department of Public Health, Oxford University, Institute of Health Sciences, Oxford.
Journal of Epidemiology & Community Health (Impact Factor: 3.5). 11/2000; 54(10):756-60.
Source: PubMed


Colorectal cancer (CRC) is a common cancer in many western countries and is probably caused in part by dietary factors. Southern European countries have lower incidence rates of CRC than many other western countries. It was postulated that, because olive oil is thought to influence bile salt secretion patterns in rats, it may influence the occurrence of CRC. The purpose of this study was to compare national levels of dietary factors, with particular reference to olive oil, with national differences in CRC incidence.
Ecological study using existing international databases. Incidence rates for CRC, food supply data, and olive oil consumption data were extracted from published sources, combined, and analysed to calculate the correlations between CRC and 10 dietary factors. Associations were then explored using stepwise multiple regression.
28 countries from four continents.
76% of the intercountry variation in CRC incidence rates was explained by three significant dietary factors-meat, fish and olive oil-in combination. Meat and fish were positively associated, and olive oil was negatively associated, with CRC incidence.
Olive oil may have a protective effect on the development of CRC. The proposed hypothesis is that olive oil may influence secondary bile acid patterns in the colon that, in turn, might influence polyamine metabolism in colonic enterocytes in ways that reduce progression from normal mucosa to adenoma and carcinoma.

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Available from: Valerie Seagroatt, May 01, 2014
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    • "From ecologic comparison of 28 countries, 76% of the inter-country variation in colorectal cancer incidence rates could be attributed to three dietary factors: meat, fish and olive oil, in combination; meat and fish were found positively associated, whereas olive oil was negatively associated. The authors stated that olive oil could influence secondary bile acid patterns in the colon that, in turn, might influence polyamine metabolism in colonic cells reducing possibility to progression from normal mucosa to adenoma and, eventually, carcinoma [80]. Also, olive oil seems to be inversely associated with breast cancer risk, although there are no robust data to consider. "
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    • "Increasingly more research is being conducted into the potential health benefits of eating fish, with evidence to suggest that dietary fish may play a protective role in diseases including cardiovascular disease, cancer, asthma and atopy (Caygill et al., 1996; Marckmann and Gronbaek 1999; Kobayashi et al., 1999; Stoneham et al., 2000; Kris-Etherton et al., 2002; Devereux and Seaton, 2003). The mechanism for this benefit has been proposed to be related to the content of omega-3 fatty acids in fish. "
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    • "Cumulative evidence have showed a role of nutritional factors in the etiology of chronic diseases (Keys, 1970; World Cancer Research Fund, 1997), suggesting a linkage between dietary patterns and increased human longevity (Farchi et al., 1995; Osler and Schroll, 1997; Lasheras et al., 2000; Kant et al., 2000; Osler et al., 2001; Trichopoulou et al., 2003). Higher levels of consumption of olive oil are considered the hallmark of the traditional Mediterranean diet, and increasing evidence suggests that olive oil, with its high levels of monounsaturated fatty acids (MUFA) and polyphenolic compounds, have a role in the prevention of coronary artery disease (CAD) (Keys, 1970), several types of cancer (Wolk et al., 1998; Stoneham et al., 2000), and it is inversely associated with both systolic and diastolic blood pressure (Psaltopoulou et al., 2004). Furthermore, we found that in an older population of Southern Italy with a typical Mediterranean diet, high MUFA energy intake appeared to be associated with a high protection against age-related cognitive decline (Solfrizzi et al., 1999; Capurso et al., 2003; Solfrizzi et al., 2003; Panza et al., 2004). "
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