Studies associate alcohol consumption, cigarette smoking, and body size with the risk of overall or subtype lymphoma. Current data come mostly from case-control studies or prospective studies with few cases. In the prospective National Institutes of Health-former American Association of Retired Persons (NIH-AARP) Diet and Health Study, the authors assessed the above lifestyle factors via baseline questionnaire among 285,079 men and 188,905 women aged 50-71 years and ascertained histologically confirmed Hodgkin's lymphoma (n = 58) and non-Hodgkin's lymphoma (n = 1,381) cases through linkage with cancer registries from 1995 to 2000. Compared with nondrinkers, alcohol consumers had a lower risk for non-Hodgkin's lymphoma overall (for >28 drinks/week: adjusted relative risk (RR) = 0.77, 95% confidence interval (CI): 0.59, 1.00; p(trend) among drinkers = 0.02) and for its main subtypes. Compared with never smokers, current smokers and recent quitters (<or=4 years ago) had higher risk of Hodgkin's lymphoma (RR = 2.25, 95% CI: 1.04, 4.89; RR = 4.20, 95% CI: 1.94, 9.09, respectively), whereas current or former smokers had lower risk of follicular non-Hodgkin's lymphoma (RR = 0.67, 95% CI: 0.52, 0.86). Severe obesity (body mass index of >or=35: RR = 1.29, 95% CI: 1.02, 1.64) and taller height (RR = 1.19, 95% CI: 1.03, 1.38) were associated moderately with non-Hodgkin's lymphoma. These findings add to the evidence that lifestyle factors and relevant anthropometric characteristics play a role in lymphoma etiology.