Substance guides

Alcohol and the immune system: Why drinkers get sick more

Published November 8, 2024 · 7 min read · Updated April 2026

Reviewed for accuracy by licensed clinical professionals.

Chronic alcohol use significantly impairs every branch of the immune system, increasing susceptibility to infections and slowing recovery.

How alcohol weakens immunity

Disrupts gut microbiome (first line of defense). Impairs white blood cell function. Reduces T-cell and B-cell effectiveness. Increases intestinal permeability (leaky gut). Promotes chronic inflammation while suppressing acute immune response.

Clinical consequences

Increased pneumonia risk (3-7x higher in heavy drinkers). Increased tuberculosis risk. Slower wound healing. Higher surgical complication rates. Increased cancer risk (immune surveillance impairment).

Recovery

Immune function begins improving within days of abstinence. Significant recovery within weeks with proper nutrition. Gut microbiome restoration over 3-6 months.

Authoritative sources

This article references guidelines from: NIDA · SAMHSA · CDC

Frequently asked questions

Does alcohol weaken your immune system?

Yes significantly. Every branch of immune function is impaired by chronic heavy drinking.

How long to recover immunity after quitting?

Initial improvement within days. Significant recovery within weeks. Full restoration over months.

Can drinking cause you to get sick more often?

Yes. Heavy drinkers are 3-7x more likely to develop pneumonia and have increased risk of many infections.

Disclaimer: Informational only. Not medical advice. SAMHSA: 1-800-662-4357.