Alcohol's Effects on the Body: Organ-by-Organ Damage from Chronic Use

Alcohol Use Disorder: A Multi-System Disease

Chronic heavy alcohol consumption (>14 drinks/week men, >7 women) damages nearly every organ system. Effects are dose- and duration-dependent, with genetic/epigenetic modifiers.

Organ-Specific Damage

1. Liver (Primary Target)

• Steatosis (fatty liver): >90% of heavy drinkers. Reversible with abstinence.
• Alcoholic hepatitis: Inflammation, Mallory bodies, neutrophilic infiltrate. Can be acute/severe (Maddrey DF ≥32 → steroids).
• Cirrhosis: Irreversible fibrosis, nodular regeneration. Portal hypertension → varices, ascites, encephalopathy. 10–20% of heavy drinkers.
• HCC: Cirrhosis = major risk factor.

2. Brain & Nervous System

• Neurotoxicity: Cortical atrophy (frontal > parietal), cerebellar degeneration (ataxia), white matter loss.
• Wernicke-Korsakoff Syndrome: Thiamine (B1) deficiency → Wernicke's (ophthalmoplegia, ataxia, confusion) → Korsakoff's (anterograde amnesia, confabulation). Emergency: IV thiamine before glucose.
• Peripheral neuropathy: Length-dependent, axonal (nutritional + toxic).
• Cognitive impairment: Executive dysfunction, memory deficits — partially reversible with abstinence.

3. Cardiovascular

• Alcoholic cardiomyopathy: Dilated, reduced EF → heart failure. Dose-related.
• Arrhythmias: Atrial fibrillation ("holiday heart"), ventricular ectopy.
• Hypertension: Dose-dependent; reverses with abstinence.
• Stroke risk: Both ischemic (AF, hypertension) and hemorrhagic.

4. Pancreas

• Acute pancreatitis: Alcohol = 2nd leading cause (after gallstones). Premature trypsin activation.
• Chronic pancreatitis: Fibrosis, calcifications, exocrine/endocrine insufficiency (diabetes, malabsorption).

5. GI Tract

• Esophagus: Reflux (LES relaxation), Barrett's, squamous cell carcinoma (synergy with smoking).
• Stomach: Gastritis, erosions, delayed healing.
• Intestines: Malabsorption (B12, folate, fat), diarrhea, bacterial overgrowth, increased permeability ("leaky gut").

6. Kidneys

• Acute kidney injury (rhabdo, hepatorenal, volume depletion).
• Chronic: Hypertension, direct tubular toxicity, ↑ uric acid.

7. Reproductive

• Men: Hypogonadism (↓ testosterone, ↑ estrogen), testicular atrophy, ED, infertility.
• Women: Menstrual irregularity, anovulation, infertility, ↑ breast cancer risk.
• Pregnancy: FASD — no safe level.

8. Immune System

• Impaired neutrophil/macrophage function, ↓ T/B cell production, ↓ IgA.
• ↑ Risk: Pneumonia, TB, post-surgical infections, poor vaccine response.

9. Cancer (Group 1 Carcinogen)

• Oropharynx, larynx, esophagus, liver, colorectum, breast (linear dose-response).

10. Skin & Musculoskeletal

• Flushing, rosacea, psoriasis exacerbation, porphyria cutanea tarda.
• Osteoporosis (↓ osteoblasts, ↑ cortisol, ↓ vitamin D/calcium absorption).
• Myopathy (proximal weakness, elevated CK).

Recovery Potential

• Liver: Steatosis → weeks; fibrosis → years/partial; cirrhosis → limited.
• Brain: Volume recovery in months; cognitive improvement in 1 yr.
• Heart: EF improves with abstinence (if not end-stage).
• Pancreas: Pain may persist; exocrine function rarely fully recovers.

Abstinence is the only disease-modifying intervention. Early intervention preserves more function.