Alcohol-Related Diseases: Organ Systems Affected and Risk Magnitude

Alcohol (ethanol) is a Group 1 carcinogen and a causal factor in >200 disease/injury conditions (WHO). Risk is dose-dependent; no safe threshold for cancer.

Liver

• Alcoholic fatty liver (steatosis) → steatohepatitis (ASH) → fibrosis → cirrhosis (irreversible).
• Cirrhosis → portal hypertension, HCC, liver failure.
• Threshold: >30 g/day (men), >20 g/day (women) for significant risk.

Cardiovascular

• Hypertension (dose-linear).
• Atrial fibrillation (↑ risk even at 1 drink/day).
• Cardiomyopathy (dilated) – heavy chronic use.
• Stroke (ischemic & hemorrhagic).
• No net cardiovascular benefit at any dose (Mendelian randomization studies).

Cancer (Causal, IARC Group 1)

• Oral cavity, pharynx, larynx, esophagus (squamous cell).
• Liver (HCC).
• Breast (linear ↑ risk from <1 drink/day).
• Colorectal.
• Mechanisms: Acetaldehyde (DNA adducts), oxidative stress, hormonal (estrogen), solvent for carcinogens.

Pancreas

• Acute & chronic pancreatitis (dose-related).
• Alcohol + smoking = synergistic risk.

Neurological

• Peripheral neuropathy (thiamine deficiency, direct toxicity).
• Cerebellar degeneration (ataxia).
• Wernicke-Korsakoff syndrome (thiamine deficiency).
• Cognitive decline, dementia (alcohol-related brain damage).
• Stroke (see CV).

Mental Health

• Depression, anxiety (bidirectional: self-medication → worsening).
• Suicide risk ↑ (acute intoxication + chronic).
• Alcohol use disorder (AUD) – 10–15% lifetime prevalence.

Nutritional

• Thiamine, folate, B12, B6, magnesium, zinc deficiency.
• Malabsorption (pancreatic, mucosal).

Social & Injury

• Trauma (MVC, falls, violence, drowning).
• Fetal alcohol spectrum disorders (FASD).
• Workplace/family dysfunction.

Risk Reduction

• Abstinence eliminates alcohol-attributable risk.
• Low-risk limits (NIAAA): Men ≤14 drinks/week, ≤4/day; Women ≤7/week, ≤3/day.
• Screening (AUDIT-C) + brief intervention in primary care.

Alcohol harms nearly every organ system. The "J-curve" for CVD is confounded; current evidence supports less is better, none is best for health.