A major European study has found that drinking even one glass of wine or beer every day raises your risk of bowel cancer by around 10 per cent. And the risk goes up the more alcohol you drink. For example, drinking more than 30 grams of alcohol a day, about one litre or nearly two pints of strong lager, increases the risk by 25 per cent.
The study, which covered nearly half a million people and involved researchers from Denmark, France, Germany, Greece, Italy, The Netherlands, Spain, Sweden, and the UK, is published in the early online edition of the International Journal of Cancer.
The researchers examined records of 478,732 participants who were free of cancer when they enrolled in the European Prospective Investigation into Cancer and Nutrition (EPIC) study between 1992 and 2000. The participants were followed up for an average of 6.2 years, during which time records showed that 1,833 of them developed colorectal cancer (CRC).
All the participants filled in questionnaires about their alcohol consumption at point of enrollment, and lifetime consumption data was also available for 69 per cent of them.
When they analysed the link between lifetime alcohol consumption and incidence of CRC, the scientists found that:
- Lifetime alcohol consumption was positively linked to CRC risk.
- The hazard ratio calculation showed an 8 per cent increase in CRC risk for each 15g per day increase in alcohol consumption.
- The risk was greater for cancer in the rectum (12 per cent per 15g per day of alcohol increase) than for cancer in the distal colon (8 per cent) and proximal colon (2 per cent).
The researchers found similar results in the link between daily alcoholic beverage consumption at time of enrollment (baseline) and CRC risk:
- Beer drinkers who drank 20 to 39.9 grams of alcohol a day had a 38 per cent higher risk of CRC compared to those who drank a negligible amount (0.1 to 2.9 grams) every day.
- For wine drinkers drinking 20 to 39.9 grams of alcohol a day led to a 21 per cent higher risk of CRC compared to drinking hardly any.
- Although the risk of CRC among wine drinkers for the same amount of daily alcohol appears to be lower, the difference was not found to be statistically significant said the researchers.
Another interesting result was the effect of diet on the link between alcohol consumption and bowel cancer.
The risk of colorectal cancer was significantly higher in those people whose diet was low in folate (13 per cent higher risk per 15g a day increase in alcohol intake at baseline, compared to only 3 per cent for those with high folate diet).
Folate, also called folic acid, is a water soluble form of vitamin B9 and is present in green leafy vegetables such as spinach and turnip greens, as well as pulse foods like beans and lentils, and seeds such as sunflower seeds. Liver is also a rich source, as is fortified cereals.
The researchers concluded that:
“In this large European cohort, both lifetime and baseline alcohol consumption increase colon and rectum cancer risk, with more apparent risk increases for alcohol intakes greater than 30 g/day.”
The lifetime risk of colorectal cancer for women is about 1 in 18, and for men it is 1 in 20. According to Cancer Research UK, over 30,000 new cases of colorectal cancer are diagnosed in the UK every year.
The lifetime risk for bowel cancer is one in 20 for men, and one in 18 for women.
An epidemiologist at Cancer Research UK, and deputy director of the cancer epidemiology unit in Oxford, UK, Prof Tim Key, told the BBC this research showed quite clearly that: “The more alcohol you drink the greater your risk of bowel cancer.”
“The increase in risk is not large but it is important that people understand they can reduce their risk of a number of different cancers, including bowel cancer, by cutting down on alcohol,” he added.
“Lifetime and baseline alcohol intake and risk of colon and rectal cancers in the European prospective investigation into cancer and nutrition (EPIC) (p NA).”
Pietro Ferrari, Mazda Jenab, Teresa Norat, Aurelie Moskal, Nadia Slimani, Anja Olsen, Anne Tjønneland, Kim Overvad, Majken K. Jensen, Marie-Christine Boutron-Ruault, Sabine Rohrmann, Jakob Linseisen, Heiner Boeing, Manuela Bergmann, Dimitra Kontopoulou, Antonia Trichopoulou, Christina Kassapa, Giovanna Masala, Vittorio Krogh, Paolo Vineis, Salvatore Panico, Rosario Tumino, Carla H. van Gils, Petra Peeters, H. Bas Bueno-de-Mesquita, Marga C. Ocké, Guri Skeie, Eiliv Lund, Antonio Agudo, Eva Ardanaz, Dolores C. López, Maria-Jose Sanchez, José R. Quirós, Pilar Amiano, Göran Berglund, Jonas Manjer, Richard Palmqvist, Bethany Van Guelpen, Naomi Allen, Tim Key, Sheila Bingham, Mathieu Mazuir, Paolo Boffetta, Rudolf Kaaks, Elio Riboli, Françoise Clavel-Chapelon, Sophie Morois.
International Journal of Cancer Published Online: 19 Jul 2007
Written by: Catharine Paddock