Health and cancer risks associated with low levels of alcohol consumption
Comment
Key messages
It is the alcohol that causes harm, not the beverage
Ethanol (alcohol) causes cancer through biological mechanisms as the compound breaks down in the body, which means that any beverage containing alcohol, regardless of its price and quality, poses a risk of developing cancer.
World Health Organization
Alcohol is a toxic, psychoactive, and dependence-producing substance and has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer decades ago – this is the highest risk group, which also includes asbestos, radiation and tobacco.
Alcohol causes at least seven types of cancer, including the most common cancer types, such as bowel cancer and female breast cancer. Ethanol (alcohol) causes cancer through biological mechanisms as the compound breaks down in the body, which means that any beverage containing alcohol, regardless of its price and quality, poses a risk of developing cancer.
Latest available data indicate that half of all alcohol-attributable cancers in the WHO European Region are caused by “light” and “moderate” alcohol consumption… This alcohol use pattern is responsible for the majority of alcohol-attributable breast cancers in women, with the highest burden observed in countries of the European Union (EU).
World Health Organization
The risk of developing cancer increases substantially the more alcohol is consumed. However, latest available data indicate that half of all alcohol-attributable cancers in the WHO European Region are caused by “light” and “moderate” alcohol consumption – less than 1.5 litres of wine or less than 3.5 litres of beer or less than 450 millilitres of spirits per week. This alcohol use pattern is responsible for the majority of alcohol-attributable breast cancers in women, with the highest burden observed in countries of the European Union (EU). In the EU, cancer is the leading cause of death – with a steadily increasing incidence rate – and the majority of all alcohol-attributable deaths are due to different types of cancers.
Risks start from the first drop
To identify a “safe” level of alcohol consumption, valid scientific evidence would need to demonstrate that at and below a certain level, there is no risk of illness or injury associated with alcohol consumption.
The new WHO statement clarifies: currently available evidence cannot indicate the existence of a threshold at which the carcinogenic effects of alcohol “switch on” and start to manifest in the human body.
Moreover, there are no studies that would demonstrate that the potential beneficial effects of light and moderate alcohol use on cardiovascular diseases and type 2 diabetes outweigh the cancer risk associated with these same levels of alcohol consumption for individual consumers.
We cannot talk about a so-called safe level of alcohol use,” explains Dr Carina Ferreira-Borges, acting Unit Lead for Noncommunicable Disease Management and Regional Advisor for Alcohol and Illicit Drugs in the WHO Regional Office for Europe, as per WHO press release.
It doesn’t matter how much you drink – the risk to the drinker’s health starts from the first drop of any alcoholic beverage. The only thing that we can say for sure is that the more you drink, the more harmful it is.”
Dr Carina Ferreira-Borges, acting Unit Lead for Noncommunicable Disease Management and Regional Advisor for Alcohol and Illicit Drugs, WHO Regional Office for Europe
Despite this, the question of beneficial effects of alcohol has been a contentious issue in research for years.
Potential protective effects of alcohol consumption, suggested by some studies, are tightly connected with the comparison groups chosen and the statistical methods used, and may not consider other relevant factors”, clarifies Dr Jürgen Rehm, Senior Scientist at the Institute for Mental Health Policy Research and the Campbell Family Mental Health Research Institute at the Centre for Addiction and Mental Health, Toronto, Canada, as per WHO press release.
Dr Jürgen Rehm, member of the WHO Regional Director for Europe’s Advisory Council for NCDs and Senior Scientist at the Institute for Mental Health Policy Research and the Campbell Family Mental Health Research Institute at the Centre for Addiction and Mental Health, Toronto, Canada
Importance of seeing the bigger picture
Globally, the WHO European Region has the highest alcohol consumption level and the highest proportion of alcohol users in the population. Over 200 million people in the Region are at risk of developing alcohol-attributable cancer.
Disadvantaged and vulnerable populations have higher rates of alcohol-related death and hospitalization, as harms from a given amount and pattern of alcohol use are higher for poorer alcohol users and their families than for richer alcohol users in any given society.
So, when we talk about possible so-called safer levels of alcohol consumption or about its protective effects, we are ignoring the bigger picture of alcohol harm in our Region and the world,” explains Dr Carina Ferreira-Borges, acting Unit Lead for Noncommunicable Disease Management and Regional Advisor for Alcohol and Illicit Drugs in the WHO Regional Office for Europe, as per WHO press release.
Although it is well established that alcohol can cause cancer, this fact is still not widely known to the public in most countries. We need cancer-related health information messages on labels of alcoholic beverages, following the example of tobacco products; we need empowered and trained health professionals who would feel comfortable to inform their patients about alcohol and cancer risk; and we need overall wide awareness of this topic in countries and communities.”
Dr Carina Ferreira-Borges, acting Unit Lead for Noncommunicable Disease Management and Regional Advisor for Alcohol and Illicit Drugs, WHO Regional Office for Europe
Comment in full text
The overall risks and harms resulting from alcohol consumption have been systematically assessed and are well documented. According to the latest WHO estimates, alcohol consumption contributed to 3 million deaths in 2016 globally and was responsible for 5.1% of the global burden of disease and injury. Alcohol consumption is associated with an increased risk of many health conditions and is the main and sufficient cause for several disorders, including alcohol dependence, liver cirrhosis, and several other non-communicable diseases and mental health conditions.
Alcohol use is among the leading risk factors for premature mortality and disability because of its causal relationship with multiple health conditions, which also include non-intentional injuries and suicides.
World Health Organization
Alcohol use is among the leading risk factors for premature mortality and disability because of its causal relationship with multiple health conditions, which also include non-intentional injuries and suicides. Younger people are disproportionately affected by alcohol compared with older people, and 13.5% of all deaths among those aged 20–39 years are attributed to alcohol. Disadvantaged and vulnerable populations have increased rates of alcohol-related death and hospitalisation.
Alcohol, as classified by the International Agency for Research on Cancer, is a toxic, psychoactive, and dependence-producing substance and a Group 1 carcinogen that is causally linked to seven types of cancer, including oesophagus, liver, colorectal, and breast cancers. Alcohol consumptions is associated with 740,000 new cancer cases each year globally.
In the EU, light to moderate alcohol consumption (<20 g of pure alcohol per day, which is equivalent to consumption of approximately <1.5 L of wine [12% alcohol by volume; ABV], <3.5 L of beer [5% ABV], or <450 mL of spirits [40% ABV] per week) was associated with almost 23,000 new cancer cases in 2017, accounting for 13.3% of all alcohol-attributable cancers and for 2.3% of all cases of the seven alcohol-related cancer types. Almost half of these cancers (approximately 11,000 cases) were female breast cancers.
Also, more than a third of the cancer cases attributed to light to moderate alcohol use (approximately 8500 cases) were associated with a light alcohol use level (<10 g per day).
Increasing levels of alcohol use are associated with increasing levels of risk of illness and mortality, leading to the question of whether a safe level of alcohol consumption that is associated with zero risk of health consequences can be defined. To identify a safe level of alcohol consumption, scientific evidence is required to show the absence of increased risk of illness or injury associated with alcohol consumption at and below that level. Some, but not all, studies have suggested that light alcohol consumption could have a small protective effect, as measured by the risk of some cardiovascular diseases or type 2 diabetes. Some studies show the existence of such effects on certain types of cardiovascular diseases in middle-aged and older people. However, several reviews also found that the protective effects of moderate consumption disappear with heavy episodic alcohol use, which increases the risk of any cardiovascular diseases.
No studies have shown that the potential existence of a protective effect for cardiovascular diseases or type 2 diabetes also reduces the risk of cancer for an individual consumer. Evidence does not indicate the existence of a particular threshold at which the carcinogenic effects of alcohol start to manifest in the human body. As such, no safe amount of alcohol consumption for cancers and health can be established. Alcohol consumers should be objectively informed about the risks of cancer and other health conditions associated with alcohol consumption.
The authors declare no competing interests. All authors are staff members of WHO. The authors alone are responsible for the views expressed here and these do not necessarily represent the decisions or the stated policy of WHO.