Background: The alcohol dehydrogenase 1B (ADH1B) genotype affects the risk for alcoholism, with elevated prevalence of a protective allele in Jews. Alcohol consumption is increasing among younger Israeli Jews, reflecting environmental influences. We investigated whether the relationship of ADH1B genotype with alcohol consumption differed between younger and older adult Israelis. Methods: Israeli community residents aged 22 to 65 participated in a structured interview that included questions on the maximum number of drinks on an occasion (Maxdrinks). The ADH1B genotype was determined for 68 participants and dichotomized into nonprotective (ADH1B*1/1) and protective (ADH1B*1/2 or ADH1B*2/2) genotypes. Using Maxdrinks as the dependent variable, Poisson's regression was used to test an age x genotype interaction. Results: The ADH1B genotype interacted significantly with age (p=0.01) in a Poisson's model with Maxdrinks as the outcome. Among participants ≥33 years, Maxdrinks was low and unrelated to the ADH1B genotype. Among participants <33 years with ADH1B*1/2 or ADH1B*2/2, Maxdrinks was also low (mean, 2.6 drinks) but among those with ADH1B*1/1, Maxdrinks was substantially higher (mean, 6.2 drinks). Conclusion: Maximum lifetime drinking among younger adult Israelis without genetic protection exceeded thresholds for risky and unsafe drinking (≥5 drinks). Environmental influences promoting greater drinking among younger Israelis may particularly affect those with the nonprotective, more common ADH1B genotype.