does alcohol increase risk of bowel cancer?

Fake news alert: Express "Bowel and gullet cancer: Just two beers or glasses of wine raises your risk"

Fake news

Fake news alert

Another piece of exaggerated reporting from the British media when it comes to alcohol and cancer. 

On  July 4th, the UK's Express newspaper reported that "Bowel and gullet cancer: Just two beers or glasses of wine 'raises your risk'" - TWO beers or glasses of wine a day raises the risk of bowel and gullet cancer by more than a fifth, according to new research

Reporting that:

Britons down an average of 2.1 drinks daily, placing them among the most vulnerable to two of the deadliest forms of the disease. And anyone having four or more drinks a day is at increased risk of liver, gastric and pancreatic cancer three more particularly lethal types.

The five cancers are the most common digestive cancers across the world, causing almost three million deaths a year, says the report by medical group United European Gastroenterology.

“Heavy” drinkers who get through more than four daily were more likely to develop pancreatic, liver and gastric cancer.

Drinking across the region is higher than in any other area in the world, with over one fifth of the European population over the age of 15 drinking heavily at least once a week. As a result, the continent suffers from the highest proportion of ill health and premature death directly linked to alcohol.

So what are the facts about Bowel and gullet cancer and alcohol?

When you do drink moderate amounts of alcohol, studies have shown that the risk of some cancers increase, yet others decrease. There is much debate about this but overall the health benefits of moderate alcohol drinking are such that your risk of dying is reduced. See more at:

WCRF Report Alcohol and risk of Colorectal Cancer

The most recent WCRF (World Cancer Research Fund) report states that "The evidence that consumption of alcohol of more than 30g/day of ethanol from alcoholic drinks is a cause of colorectal cancer in men is convincing, and probably also in women."

So when you read the summary the WCRF seems damning, but the devil is in the detail and things aren't what they seem at first read! It is a very mixed picture.

A wine at 12.5 % vol contains 12.5ml of alcohol/100ml of wine x 0.8 g/ml = 10g of alcohol/100 ml of wine. So 30g is 300ml, around half a bottle a day (A drinking unit can vary from 8-14g of alcohol depending on the country). For example, 125 ml of wine (12.5% vol), will translate into 1.25 drinking units and 175ml of wine (12.5% vol), will translate into 1.75 drinking units.

Your lifetime Risk of Developing colon and rectum cancer is approximately 4.3 percent of men and women (diagnosed with  at some point during their lifetime, based on 2012-2014 data).

Relative risk, your additional chance of getting bowel cancer, has been reported as follows and summarised by the WCRF in their report. If relative risk is 1.25, your lifetime risk is 5.4%. If relative risk is 1 your lifetime risk is unchanged at 4.3%.

Kato 1999 (1 = no additional risk), Ford 1997 (0.97 =slightly reduced risk, Schoen 1999 (1.24 = 24% higher chance), Chen 2001 (1.26), Flood 2002 (1.02 = no increased risk), Pedersen 2003 (1.0).

The summary estimate is 1.01 according to WCRF= no increased risk of colorectal cancer with Alcohol! 

Somewhat different to the summary, "The evidence that consumption of alcohol of more than 30g/day of ethanol from alcoholic drinks is a cause of colorectal cancer in men is convincing, and probably also in women." Hardly convincing evidence of increased risk. I would say no risk increased risk based on the data!

Summary: Is it true Bowel and gullet cancer: Just two beers or glasses of wine 'raises your risk'?

The most respected cancer reporting charity the WCRF has concluded that the the relative risk is the same for drinkers as non drinkers. So the Express newspapers claims that "just two beers or glasses of wine raises your risk" is untrue. Fake news! 

Further information: Detailed summary of bowel cancer studies

See more at: 

Cho et al in 2004 in their paper "Alcohol intake and colorectal cancer: a pooled analysis of 8 cohort studies" saw that "In categorical analyses, increased risk for colorectal cancer was limited to persons with an alcohol intake of 30 g/d or greater (approximately > or =2 drinks/d), a consumption level reported by 4% of women and 13% of men. "

In 2007, Ferrari et al reported on the link between rectal and colon cancers in Europe concluding 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 2009 Park JY et al with participants from Norfolk concluded that "Total alcohol consumption was not associated with CRC risk before or after adjustment for age, sex, weight, height, and smoking status . No significant associations were observed between consumption of specific alcoholic beverages (beer, sherry, or spirits) and CRC risk when compared with non-drinkers after adjustment for lifestyle and dietary factors. Daily consumption of > or =1 unit of wine appeared inversely related to CRC risk (HR: 0.61, 95% CI: 0.40-0.94). No evidence was found for sex-specific relationships, and further exclusion of cases incident within 3 years of baseline did not change the associations observed. In this population-based UK cohort, we did not find any significant adverse effect of alcohol over the moderate range of intake on colorectal cancer risk.". So a 40% lower risk with daily consumption of wine!

In the 2010 UK study by Park et al, which looked at alcohol intake and risk of colorectal cancer (CRC) concluded that "No clear associations were observed between site-specific CRC risk and alcohol intake in either sex. " (up to 30g/day).

Hjartaker et al in 2013 looked at "subsite specific dietary risk factors for Colorectal cancer: A review of cohort studies" . The paper stated that "Ten articles were included in the review. Three analyses for both sexes combined consistently showed a higher risk of rectal cancer with increasing alcohol consumption and no significant associations for any of the colon subsites . In the EPIC studyan increased risk was reported both for rectal and distal colon cancer, whereas in the UK dietary cohort consortium (part of which is included in the EPIC study) a significantly increased risk was found for distal colon cancer only."