Alcohol Metabolism, Effects, and Health Risks: A Comprehensive Overview

Absorption and Metabolism

Alcohol is absorbed primarily in the stomach (20%) and small intestine (80%). Rate depends on concentration, food presence (slows absorption), body weight, sex, and genetics. Blood alcohol concentration (BAC) peaks 30–90 minutes post-ingestion.

Hepatic Processing

In the liver, alcohol dehydrogenase (ADH) converts ethanol to acetaldehyde (toxic), then aldehyde dehydrogenase (ALDH) converts acetaldehyde to acetate. Acetate enters the citric acid cycle, yielding water, CO₂, and energy. Genetic variants in ADH/ALDH affect tolerance and cancer risk.

Acute Effects

Dose-dependent CNS depression: impaired judgment, coordination, reaction time. Higher doses cause nausea, vomiting, ataxia, respiratory depression, coma, or fatal alcohol poisoning.

Chronic Health Consequences

• Liver: Steatosis → steatohepatitis → fibrosis → cirrhosis → hepatocellular carcinoma.
• Cardiovascular: Hypertension, cardiomyopathy, arrhythmias, stroke.
• Cancer: Oral, pharyngeal, esophageal, liver, colorectal, breast (acetaldehyde is a Group 1 carcinogen).
• Neurological: Cognitive decline, peripheral neuropathy, Wernicke-Korsakoff syndrome (thiamine deficiency).
• Psychosocial: Relationship breakdown, job loss, financial ruin, legal problems.

Seeking Help

If you're concerned about your drinking, talk to your primary care provider. Resources include NIAAA's Treatment Navigator, SAMHSA's helpline (1-800-662-HELP), and mutual-support groups (AA, SMART Recovery).

Note: The original title mentioned smoking's impact on rheumatoid arthritis, but the source content covers only general alcohol pharmacology and risks. Smoking is not addressed.