What is the role of the immune system in alcohol-related infections?

• A. Chronic alcohol use strengthens immune function
• B. Chronic alcohol use enhances immune response
• C. Chronic alcohol use impairs immune function, increasing susceptibility to infections.
• D. Immune system only affected in first week of heavy drinking

Answer: (C)

Chronic alcohol use impairs immune function, increasing susceptibility to infections. Heavy, long-term drinking disrupts both innate and adaptive defenses. Neutrophils and macrophages don’t respond as effectively—their ability to move to sites of infection and to engulf and destroy pathogens is reduced. The lining of the gut becomes more permeable, allowing bacteria and endotoxins to enter the bloodstream, which can overstimulate and then fatigue the immune system. Cytokine signaling can become imbalanced, and there’s diminished activity of T cells and natural killer cells, weakening the body’s targeted immune responses. Nutritional deficiencies and sleep disruption often accompanying chronic drinking further weaken immunity, compounding the risk. All of this means infections are more likely and can be more severe, with higher risks for illnesses like pneumonia and bloodstream infections.

The idea that alcohol strengthens immune function isn’t supported by what we know about how the immune system responds to chronic exposure. And immune impairment from long-term heavy use isn’t limited to just the first week of drinking; the risk persists with ongoing alcohol abuse and can take time to recover even after stopping.