When it comes to our overall health and well-being, we often overlook the intricate relationship between what we consume and the state of our gut. The gut is not only responsible for digestion but also plays a crucial role in our immune system, mental health, nutrient absorption, and many other things. Alcohol consumption has become deeply ingrained in social gatherings and everyday life. Some alcohol use has been touted as “heart-healthy” or a tool in preventing disease due to the plant compounds found in red grapes, such as resveratrol. How does alcohol impact our health and our digestive system? Here we explore the effects of alcohol consumption on gut health, focusing on conditions such as leaky gut, inflammation, and impaired nutrient absorption.

The Mechanics of it All:

Ethanol, the primary component of alcoholic beverages, is responsible for the effect of alcohol on the gut. When alcohol is consumed, enzymes primarily in the liver, but also in other tissues like the brain and gut, metabolize ethanol into a toxic, known carcinogen called acetaldehyde. While acetaldehyde is quickly converted to acetate, it has the potential to cause significant cellular damage leading to inflammation or heightened immune response, oxidative stress, and DNA damage.

Disruption of Gut Barrier Function:

Alcohol disrupts the integrity of the gut barrier, which is primarily maintained by tight junction proteins. These proteins create a physical barrier between the cells lining the intestinal wall, preventing the passage of harmful substances into the bloodstream. Ethanol and acetaldehyde interfere with these tight junction proteins’ function, increasing gut lining permeability. Consequently, this disruption allows the entry of toxins, bacteria, and undigested food particles into the bloodstream, triggering an immune response and inflammation.

Common symptoms associated with gut barrier dysfunction include digestive symptoms like bloating, gas, diarrhea or constipation, food sensitivities, fatigue, joint pain, skin issues, anxiety, depression, and even autoimmune conditions like Hashimoto’s and Celiac Disease.

Gut Microbiome Imbalance:

Alcohol consumption alters the composition and diversity of the gut microbiome. Studies have shown that alcohol use can decrease beneficial bacteria, such as Lactobacillus and Bifidobacterium, while increasing the abundance of harmful bacteria, like Enterococcus and E. coli. This microbial imbalance, known as dysbiosis, affects the production of essential by-products and short-chain fatty acids, impacting gut health.

In addition, many gut bacteria are responsible for the synthesis of neurotransmitters, such as GABA, serotonin, dopamine, and norepinephrine, that regulate mood and mental health. Dysbiosis of gut bacteria induced by alcohol consumption has been linked to increased anxiety, depression and cognitive impairment.

Increased Gut Inflammation:

When you consume alcohol, it can cause inflammation, which means that your gut becomes irritated and inflamed. One way that alcohol causes this inflammation is by activating a specific pathway in your cells called the NF-κB pathway. This pathway is like a communication system that helps regulate your immune system and inflammation.

When the NF-κB pathway is activated by alcohol, it leads to the release of certain molecules that cause inflammation, such as TNF-alpha, IL-1β, IL-6, and IL-8. These molecules contribute to the inflammation in your gut and can potentially lead to gastrointestinal disorders. It's important to understand that the inflammation caused by alcohol is complex and involves different signals and interactions between your cells and immune system.

Altered Nutrient Absorption:

Alcohol interferes with the absorption of essential nutrients in the gut. It impairs the function of specific transporters responsible for the uptake of vitamins, minerals, and other nutrients, leading to deficiencies. For example, alcohol inhibits the absorption of thiamine (vitamin B1), folate (vitamin B9), and vitamins A, D, E, and K. This impaired nutrient absorption can have wide-ranging effects on overall health and contribute to various alcohol-related nutritional deficiencies.

Understanding these biochemical components helps shed light on how alcohol directly impacts the gut. By recognizing the specific mechanisms through which alcohol disrupts gut health, we can better comprehend the importance of moderation and adopting practices that promote a healthy gut microbiome.

Should We Drink Alcohol at All?

Of course, this is a personal decision shaped by personal goals. Every individual metabolizes alcohol differently and has its own bio-individual genome that comes with its own set of risks. In scientific literature, a moderate drinking level is considered one drink per day for women and two drinks per day for men. While this may be less than the cultural norm, in my clinical opinion, this is too much, and we should have more days than less during the week of zero alcohol.

What does this look like for me personally? My general rule of thumb is to limit alcohol to the weekends, and when I do drink, typically limit my consumption to two drinks per night. Of course, there are gatherings with friends and exceptions to this rule, but this is what works for me personally.

Reducing alcohol consumption has been a journey for me and has taken time. I suggest reflecting on the above information, removing judgment, assessing your health goals and family genetics, and coming up with a routine that works best for you.

As always, should you decide you need help with your health goals, we at GreenMind are here for you!

References:

Aleman, R. S., Moncada, M., & Aryana, K. J. (2023). Leaky Gut and the Ingredients That Help Treat It: A Review. Molecules (Basel, Switzerland), 28(2), 619. https://doi.org/10.3390/molecules28020619
Elamin, E., Jonkers, D., Juuti-Uusitalo, K., van Ijzendoorn, S., Troost, F., Duimel, H., Broers, J., Verheyen, F., Dekker, J., & Masclee, A. (2012). Effects of ethanol and acetaldehyde on tight junction integrity: in vitro study in a three-dimensional intestinal epithelial cell culture model. PloS one, 7(4), e35008. https://doi.org/10.1371/journal.pone.0035008
Fuenzalida, C., Dufeu, M. S., Poniachik, J., Roblero, J. P., Valenzuela-Pérez, L., & Beltrán, C. J. (2021). Probiotics-Based Treatment as an Integral Approach for Alcohol Use Disorder in Alcoholic Liver Disease. Frontiers in pharmacology, 12, 729950. https://doi.org/10.3389/fphar.2021.729950
Haas, E. A., Saad, M. J. A., Santos, A., Vitulo, N., Lemos, W. J. F., Martins, A. M. A., Picossi, C. R. C., Favarato, D., Gaspar, R. S., Magro, D. O., Libby, P., Laurindo, F. R. M., Da Luz, P. L., & WineFlora Study (2022). A red wine intervention does not modify plasma trimethylamine N-oxide but is associated with broad shifts in the plasma metabolome and gut microbiota composition. The American journal of clinical nutrition, 116(6), 1515–1529. https://doi.org/10.1093/ajcn/nqac286
Hillmer, A. T., Nadim, H., Devine, L., Jatlow, P., & O'Malley, S. S. (2020). Acute alcohol consumption alters the peripheral cytokines IL-8 and TNF-α. Alcohol (Fayetteville, N.Y.), 85, 95–99. https://doi.org/10.1016/j.alcohol.2019.11.005
Kawaratani, H., Tsujimoto, T., Douhara, A., Takaya, H., Moriya, K., Namisaki, T., Noguchi, R., Yoshiji, H., Fujimoto, M., & Fukui, H. (2013). The effect of inflammatory cytokines in alcoholic liver disease. Mediators of inflammation, 2013, 495156. https://doi.org/10.1155/2013/495156
Li, X., Chen, L., Kumar, G., Zhang, S., Zhong, Q., Zhang, H., Gui, G., Wu, L., Fan, H., & Sheng, J. (2022). Therapeutic Interventions of Gut-Brain Axis as Novel Strategies for Treatment of Alcohol Use Disorder Associated Cognitive and Mood Dysfunction. Frontiers in Neuroscience, 16, 820106. https://doi.org/10.3389/fnins.2022.820106
Mutlu, E. A., Gillevet, P. M., Rangwala, H., Sikaroodi, M., Naqvi, A., Engen, P. A., Kwasny, M., Lau, C. K., & Keshavarzian, A. (2012). Colonic microbiome is altered in alcoholism. American journal of physiology. Gastrointestinal and liver physiology, 302(9), G966–G978. https://doi.org/10.1152/ajpgi.00380.2011
National Institute on Alcohol Abuse and Alcoholism (NIAAA). (n.d.). Alcohol Metabolism. Retrieved from https://www.niaaa.nih.gov/publications/alcohol-metabolism#:~:text=Most%20of%20the%20ethanol%20in,CH3CHO)%2C%20a%20known%20carcinogen.
National Institute on Alcohol Abuse and Alcoholism (NIAAA). (n.d.). Gastrointestinal Microbiome: Alcohol Effects on Composition of Intestinal Microbiota. Retrieved from https://arcr.niaaa.nih.gov/alcohol-and-immune-system/gastrointestinal-microbiome-alcohol-effects-composition-intestinal-microbiota#article-toc5
Neuman M. G. (2003). Cytokines--central factors in alcoholic liver disease. Alcohol research & health : the journal of the National Institute on Alcohol Abuse and Alcoholism, 27(4), 307–316.