Dietary flavonoid intake and colorectal cancer risk in the European prospective investigation into cancer and nutrition (EPIC) cohort

• Published in: International journal of cancer 2017-04, Vol.140 (8), p.1836-1844
• Main Authors: Zamora‐Ros, Raul, Barupal, Dinesh K., Rothwell, Joseph A., Jenab, Mazda, Fedirko, Veronika, Romieu, Isabelle, Aleksandrova, Krasimira, Overvad, Kim, Kyrø, Cecilie, Tjønneland, Anne, Affret, Aurélie, His, Mathilde, Boutron‐Ruault, Marie‐Christine, Katzke, Verena, Kühn, Tilman, Boeing, Heiner, Trichopoulou, Antonia, Naska, Androniki, Kritikou, Maria, Saieva, Calogero, Agnoli, Claudia, Santucci de Magistris, Maria, Tumino, Rosario, Fasanelli, Francesca, Weiderpass, Elisabete, Skeie, Guri, Merino, Susana, Jakszyn, Paula, Sánchez, Maria‐José, Dorronsoro, Miren, Navarro, Carmen, Ardanaz, Eva, Sonestedt, Emily, Ericson, Ulrika, Maria Nilsson, Lena, Bodén, Stina, Bueno‐de‐Mesquita, H. B(as), Peeters, Petra H., Perez‐Cornago, Aurora, Wareham, Nicholas J., Khaw, Kay‐Thee, Freisling, Heinz, Cross, Amanda J., Riboli, Elio, Scalbert, Augustin
• Format: Article
• Language: English
• Subjects: Adult; Aged; Animal models; Cancer; Cancer and Oncology; Cancer och onkologi; Carcinogenesis; Cell proliferation; Cell Proliferation - drug effects; Clinical medical disciplines: 750; Clinical Medicine; Colon cancer; Colorectal cancer; Colorectal carcinoma; Colorectal Neoplasms - chemically induced; Colorectal Neoplasms - diet therapy; Colorectal Neoplasms - epidemiology; Colorectal Neoplasms - pathology; diet; Diet - adverse effects; Dietary intake; Dietary Supplements - adverse effects; EPIC; Epidemiology; Europe; Female; Flavonoids; Flavonoids - adverse effects; Flavonoids - therapeutic use; Follow-Up Studies; Glycosides; Health risk assessment; Health risks; Health Sciences; Humans; Hälsovetenskap; Klinisk medicin; Klinisk medisinske fag: 750; Male; Medical and Health Sciences; Medical disciplines: 700; Medical research; Medicin och hälsovetenskap; Medisinske Fag: 700; Middle Aged; Nutrition and Dietetics; Nutritional Status; Näringslära; Oncology: 762; Onkologi: 762; Phenols; prospective cohort; Prospective Studies; Questionnaires; Rectum; Risk Factors; Surveys and Questionnaires; Tumors; VDP; White People
• ISSN: 0020-7136; 1097-0215; 1097-0215
• DOI: 10.1002/ijc.30582

Flavonoids have been shown to inhibit colon cancer cell proliferation in vitro and protect against colorectal carcinogenesis in animal models. However, epidemiological evidence on the potential role of flavonoid intake in colorectal cancer (CRC) development remains sparse and inconsistent. We evaluated the association between dietary intakes of total flavonoids and their subclasses and risk of development of CRC, within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. A cohort of 477,312 adult men and women were recruited in 10 European countries. At baseline, dietary intakes of total flavonoids and individual subclasses were estimated using centre‐specific validated dietary questionnaires and composition data from the Phenol‐Explorer database. During an average of 11 years of follow‐up, 4,517 new cases of primary CRC were identified, of which 2,869 were colon (proximal = 1,298 and distal = 1,266) and 1,648 rectal tumours. No association was found between total flavonoid intake and the risk of overall CRC (HR for comparison of extreme quintiles 1.05, 95% CI 0.93–1.18; p‐trend = 0.58) or any CRC subtype. No association was also observed with any intake of individual flavonoid subclasses. Similar results were observed for flavonoid intake expressed as glycosides or aglycone equivalents. Intake of total flavonoids and flavonoid subclasses, as estimated from dietary questionnaires, did not show any association with risk of CRC development. What's new? While flavonoids exert powerful anticancer effects in various colorectal cancer (CRC) cell lines, whether they produce similar cancer‐fighting effects when consumed in the diet remains unclear. In this prospective cohort study in Europe, associations between dietary flavonoid intake and CRC risk were evaluated based on intake of total flavonoids and flavonoid subclasses, expressed as glycosides and aglycones. Neither total flavonoid intake nor flavonoid intake by subclass was found to be linked to CRC risk reduction. In addition, CRC risk in relation to flavonoid intake did not vary by sex or alcohol consumption but was slightly modified by smoking status.