**Background:** Alcohol consumption is a global public health concern, causing 2.1 deaths per 100,000 persons worldwide in 2019. In Iran, alcohol is illegal and forbidden by Islam, leading to underreporting and limited population-based data. Alcoholic beverages are often homemade or obtained through the black market, increasing risks of methanol toxicity. This study aimed to provide comprehensive estimates of alcohol consumption prevalence and its association with health outcomes using a large-scale national survey.
**Methods:** The National Surveillance of Non-Communicable Risk Factors (STEPs) 2016 was a cross-sectional population-based household survey conducted across all 30 provinces of Iran. A total of 31,050 adults aged ≥18 years were selected using cluster random sampling proportional to size, based on the national postal code database. The final analytical sample for the alcohol section was 29,068 participants (response rate 93.6%). Data were collected via interviewer-administered questionnaires based on WHO guidelines, covering lifetime and current alcohol consumption, binge drinking (≥6 standard drinks per episode), and frequent heavy episodic drinking. A standard drink was defined as 10 grams of pure alcohol. Outcomes assessed included cardiac disorders, stroke, fatty liver disease (ALT > 40 U/L), injuries, and dietary habits. Weighted survey methods were used for descriptive analyses, and age-standardized rates were calculated using the 2016 national census. Multiple logistic regression models adjusted for sex, age, smoking, wealth index (derived from PCA of household assets), and physical activity.
**Key Results:** The mean age of participants was 44.4 years (range 18–100); 52.08% were female, 85.37% were non-smokers, 56.36% were physically inactive, and 71.09% lived in urban areas. At the national level, lifetime alcohol consumption prevalence was 8.00% (95% CI: 7.67–8.32) and current alcohol consumption was 4.04% (95% CI: 3.81–4.27). The highest prevalence was among 25–34 year-olds, with rates declining significantly with age (p for trend <0.001). Men had substantially higher rates than women: lifetime 15.27% vs. 1.35%, current 7.61% vs. 0.78%. Socioeconomic status was directly associated with consumption—the rich quintile had 5.6% current drinking vs. 2.6% in the poor quintile. Among current drinkers, 73.36% drank less than once per month, 14.90% drank 1–2 days per month, and only 0.20% drank daily. Binge drinking among current consumers was reported as daily (1.60%), weekly (6.49%), monthly (15.14%), and less than 12 times per year (35.03%). At the provincial level, age-standardized current alcohol consumption ranged from 0.4% (95% CI: 0–1.18) to 23.92% (95% CI: 17.56–30.28) in males, and from 0% to 1.58% (95% CI: 0.22–2.94) in females. In urban regions, the highest rate was 22 times greater than the lowest. In Tehran, current consumption was 4.27% overall (7.39% in men, 1.32% in women). In adjusted logistic regression models, current alcohol consumption was significantly associated with traffic injuries (ORadj 2.02, 95% CI: 1.75–2.35, p<0.001). Associations with cardiac disease (ORadj 1.23, 95% CI: 0.83–1.83), stroke (ORadj 0.60, 95% CI: 0.15–2.46), poor diet (ORadj 1.06, 95% CI: 0.88–1.28), and fatty liver disease (ORadj 1.05, 95% CI: 0.81–1.38) were not statistically significant after adjustment.
**Clinical Implications:** While the overall prevalence of alcohol consumption in Iran is low compared to global rates, the marked provincial and gender disparities—ranging from near-zero to nearly 24% in some male subgroups—indicate that targeted interventions are needed for high-prevalence areas. The finding that current drinkers have twice the odds of injury underscores a clinically meaningful public health burden, particularly for traffic-related harm. The lack of significant associations with cardiac disease or stroke after adjustment aligns with recent meta-analyses refuting protective effects of alcohol. Policy makers should prioritize WHO-recommended measures including public awareness campaigns, health service responses, community action, reducing alcohol intoxication, and monitoring illicit alcohol production. The study is limited by its cross-sectional design (cannot assess causality), potential underreporting due to stigma, and inability to capture detailed consumption patterns or alcohol use disorder diagnoses.