By Gina Lynem-Walker
The body’s immune system is incredibly complex and keeping it well-regulated relies on many factors — including diet, exercise and sleep. How much alcohol an individual consumes is also a factor. When the body processes alcohol, multiple organs are affected in different ways — all of which have negative impacts on the immune system. As more and more people turn to alcohol to cope with the stress of the COVID-19 pandemic, it’s important to understand the potential harmful impacts of alcohol on the body’s ability to fight off diseases.
Alcohol can affect the way different immune cells in the brain express themselves, altering the molecular pathways that regulate neuroinflammation. This is why long-term alcohol abuse can cause the brain’s neuroimmune function to become imbalanced, which could lead to riskier decisions, increased drinking or decreased behavioral flexibility.
This means drinking may signal the brain in a way that leads to alcohol use disorder and enables heavy drinking to continue.
One of the first points of contact for alcohol in the body is the gastrointestinal system, where alcohol enters the bloodstream. Here’s how that can affect the immune system:
- The number and abundance of microbes in the microbiome can be altered by alcohol, which then affect the immune system’s functionality
- The communication between organisms and the intestinal immune system can be disrupted by alcohol
- Cells in the gastrointestinal system can be damaged by alcohol, which disrupts the gut’s function as a barrier and allows bacterial products from the gut to leak out, leading to liver inflammation and potentially liver cancer
The immune system is a major factor in the development and progression of alcoholic liver disease. Alcoholic liver disease occurs after years of heavy drinking and can lead to cirrhosis. Consuming alcohol contributes to the build up of fats in the liver and is linked to diets higher in fatty foods which, in turn, also add fat to the liver.
Alcohol consumption has been linked to increased risk of pneumonia and pulmonary diseases like tuberculosis, respiratory syncytial virus and ARDS. Here’s how damaging alcohol is to the lungs:
- The cilia in the upper airways is disrupted by alcohol, which impairs the function of the immune cells there
- The epithelia barrier in the lower airways is weakened
Often, damage to the lungs from alcohol goes undetected until an individual contracts a respiratory infection, which can then lead to more severe lung diseases.
Hospitals nationwide are reporting an increase in alcohol-related admissions for liver failure and alcoholic hepatitis during the COVID-19 pandemic. The stress of disruption and uncertainty from the pandemic have caused many individuals to turn to unhealthy coping mechanisms.
These alcohol-related illnesses affect everyone differently and can show up after just months of heavy drinking. Alcohol is metabolized at different rates depending on many factors — and so one person could drink heavily without long-term side effects while another could need urgent medical care.
The relationship between alcohol and the immune system is important to understand as communities prepare to return to a more normal pace of life this spring and summer.
About the author: Gina Lynem-Walker is associate medical director at Blue Cross Blue Shield of Michigan.