Alcohol and Cancer

The Hidden Risks

For many people, enjoying an occasional alcoholic beverage is a common social practice. It can lead to a sense of calmness or conviviality for most people, that is, if it's done in moderation. We all know that too much alcohol leads to cognitive abnormalities (buzz) and eventually a stupor (otherwise known as passing out).  Heavy drinking and alcoholism are both well-established risk factors for many conditions, including cirrhosis of the liver, cardiovascular diseases, and cancer.

At this point, alcohol is classified as a carcinogen (a cancer-causing substance).  In 2020-2021, 20,000 cancer deaths in the U.S. were alcohol-attributable/year. Surprisingly, less than half of Americans recognize the significant connection between alcohol intake and an increased risk of various cancers. However, while we continue to research precisely how alcohol is linked to cancer, there is no debate that alcohol intake raises the risk of various cancers. Most notably: 

• Mouth
• Throat (pharynx)
• Voice box (larynx)
• Esophagus
• Colon and rectum
• Liver
• Breast (in women)

Heavy drinking is also associated with a higher risk of stomach and pancreatic cancers.

Overconsumption of alcohol is estimated to be the third leading preventable cause of cancer, following only smoking and obesity. 

As an aside, alcohol is a natural substance. It is produced through the fermentation of carbohydrates, which naturally occurs when yeast is exposed to fermentable sugar (example: grapes + yeast = wine). Drinking alcoholic beverages has been a common practice by cultures worldwide for millennia. So, how could a perfectly natural process, which we have been involved with for so long, possibly harm us? Good question. Let's take a look.

How is Alcohol Carcinogenic?

Several independent mechanisms may account for the carcinogenic effects of alcohol:

1. Acetaldehyde Production: When your body processes alcohol, it breaks it down into a toxic chemical called acetaldehyde. This substance can directly damage your DNA and hinder its repair processes, increasing the likelihood of cancerous mutations. Fortunately, there is an enzyme called Acetaldehyde Dehydrogenase (ALDH) that limits acetaldehyde production by converting it into a vinegar-like compound (acetate). However, if there is a large volume of alcohol consumed, then ALDH can be overwhelmed and unable to keep up with the aldehyde production. This is why drinking larger volumes of alcohol means significantly more acetaldehyde production, and this has been shown in the data. The risk of alcohol-related cancers goes up as the amount of alcohol consumed goes higher. 
2. Oxidative Stress: Alcohol consumption can elevate oxidative stress within the body, leading to cellular damage, including damage to DNA and proteins. Oxidative stress has been implicated in various types of cancer. 
3. Hormonal Changes: Alcohol can disrupt the body's hormonal balance, including increasing estrogen and testosterone levels. Elevated estrogen levels are a known risk factor for certain hormone-related cancers, such as breast cancer.
4. Microbiome Disruption: Alcohol can negatively impact the beneficial bacteria in your gut, leading to an imbalance known as dysbiosis. This disruption can increase overall inflammation in the body and potentially elevate cancer risk.
5. Vitamin Deficiencies: Heavy or chronic drinking can lead to deficiencies in essential nutrients like folate, which is essential for DNA repair and overall cellular health. Folate deficiency is a known risk factor for cancer, as well as an established vitamin deficiency in heavy drinkers.  

So why doesn't everyone who drinks a lot of alcohol get cancer?

Ah, the George Burns effect. George Burns lived to over 100 years old. He smoked cigars, drank hard liquor, and was as thin as a rail. Lest we put all the blame on the innocent molecule ethanol (the chemical name for the alcohol we drink), we need to realize that we are all biochemically different. We all have different genetic hardwiring, shaped by our ethnicities, and we also have "software" for our genes (epigenetics) that are influenced by the exposures and habits of our ancestors and ourselves. For example, some people do not have the gene necessary to make the enzyme ALDH. ALDH is the enzyme that breaks down acetaldehyde (see 1 above).  The tendency to lack this gene is higher in people from Asia. Another genetic factor at play is that many people do not activate folate well from their diet. They have the (almost comical acronym) MTHFR deficiency. MTHFR = methyltetrahydrofolate reductase. It's like starting at a disadvantage, so the alcohol-induced folate deficiency is amplified by a genetically poor ability to use folate.

Risk is seldom a stand-alone factor. When it comes to any risk factor related to exposures, infections, or any other physical interface with our cells, this is always in context with our genetic (and epigenetic) makeup.  This is why one person gets cancer and another doesn't, even when they have the same level of exposure, in this case, alcohol. 

Debunking Myths: Red Wine and Health:

The notion that drinking red wine offers significant health benefits, often attributed to the antioxidant resveratrol found in grape skins, is a common misconception. While resveratrol does possess some beneficial properties, the amount present in a typical serving of red wine is minimal and unlikely to provide substantial health advantages. Furthermore, the alcohol content itself negates any potential protective effects regarding cancer risk. The scientific consensus does not support the idea that alcohol, including red wine, offers protection against cancer or heart disease.

Sensible Alcohol Consumption:

Current guidelines suggest that if adults choose to drink, women should consume no more than one standard drink per day, and men no more than two. However, it's vital to recognize that there is no completely safe level of alcohol consumption when it comes to cancer risk. The less alcohol you consume, the lower your risk. For cancer prevention, the most prudent approach is to limit or avoid alcohol altogether. Dr. Vivek Murthy, US Surgeon General (2025), has advocated for visible warning labels on alcoholic beverages to draw greater attention to the risks.

Making Safer Choices:

Despite the risks, many individuals may still choose to consume alcohol occasionally in social settings. If you do choose to drink, here are some strategies to minimize potential harm:

• Moderate Your Intake: Strictly adhere to low-risk drinking guidelines by limiting yourself to small amounts.
• Be Mindful of Serving Sizes: Understand standard drink sizes in the U.S. (e.g., 5 ounces of wine, 12 ounces of beer, or 1.5 ounces of spirits) and be aware of how much you are actually consuming.
• Choose Mocktails: Explore delicious and sophisticated non-alcoholic mocktail recipes that can provide an enjoyable social experience without the risks associated with alcohol.
• Try Kombucha: Consider kombucha, a fermented tea, as a healthy alternative that can offer a bubbly and satisfying feel without the alcohol content.

Conclusion:

Alcohol is deeply integrated into many cultures, yet acknowledging its significant link to increased cancer risk is essential for making informed decisions about your health. Understanding the scientific relationship between alcohol and cancer can guide you toward healthier lifestyle choices. By being aware of the risks and adopting strategies for moderation or abstinence, you can take proactive steps in reducing your cancer risk and promoting long-term well-being.