Eight Drinks A Day Almost Doubles Overall Cancer Risk

A cup of beerA report, published by the Cancer Institute NSW in Australia has found that alcohol might be more strongly linked to cancer than previous thought.

The authors of the report reviewed the findings of 634 previous studies to determine the link between alcohol consumption and the risk of various cancers. In total, cancer risk was found to be 22% higher in people who consumed four alcoholic drinks a day compared to non-drinkers and 90% higher in those who consumed eight alcoholic drinks a day. On the other hand, consumption of two alcoholic drinks a day appeared to have little or no effect on cancer risk.

The researchers found conclusive evidence that moderate to heavy alcohol consumption raised the risk of cancer in the liver, breast, colon, stomach and upper-digestive tract while no link was found between alcohol and bladder, endometrial, or pancreatic cancer.

Cancers of the upper-digestive tract which includes the mouth, esophagus, larynx, and pharynx were four times more likely in those who consumed four alcoholic drinks a day and six times greater in those who consumed eight times a day compared to non-drinkers.

Breast cancer risk increased by around 10% with each additional alcoholic drink consumed, this equates to twice the risk of breast cancer for someone consuming an average of eight alcoholic drinks per day. It is believed that as many as 10% of all breast cancers might be attributable to alcohol.

Stomach cancer was only slightly associated with heavy alcohol consumption with eight drinks a day raising stomach cancer risk by around 30%.

Colo-rectal cancers did not appear to be associated with alcohol in women however heavy male drinkers were at a 60 to 80 percent greater risk of developing colo-rectal cancers than non-drinkers.

The results were the opposite for liver cancer with women drinkers appearing to be at a greater risk of liver cancer than men. Heavy male drinkers were 60% more likely to develop liver cancer while females were a massive nine times more likely to develop the disease compared to non-drinkers. Around 35% of all liver cancers are thought to be alcohol related.

Some evidence existed for a link between alcohol and prostate, kidney, lung, cervical, and ovarian cancers, however the evidence was not sufficient to draw definitive conclusions.

Many mechanisms have been proposed to explain the link between alcohol and cancer. Acetaldehyde, which is produced in the body when alcohol is metabolised, is a known carcinogen. Alcohol also impairs the bodies ability to absorb folate resulting in a folate deficiency in many heavy drinkers. Low folate levels have been implicated in the development of several forms of cancer including colo-rectal, breast, and pancreatic cancers. Alcohol is also known to increase estrogen levels which may explain its link with breast cancer.

Cancer is currently the second most common cause of death in the western world behind heart disease. Around 35% of women and almost half of all men will be diagnosed with cancer during their lifetimes and this figure is likely to rise as life expectancies continue to increase. Prostate cancer is the most common form of cancer in men while breast cancer is the most common in women.

It is thought as many as a third of all cancers are preventable through healthy lifestyle choices such as not smoking, consuming a variety of fresh fruits and vegetables, and being physically active.