There are scarce data of alcohol consumption and telomere length, an indicator of biological age. In 1974, detailed alcohol consumption was available for a socioeconomically homogenous cohort of middle-aged men (The Helsinki Businessmen Study). Their alcohol use, divided into 5 groups (zero, 1-98, 99-196, 197-490, >490 g/week) has been repeatedly assessed until old age. In 2002/2003, leukocyte telomere length (LTL) and the proportion of short telomeres (less than 5 kilobases) were measured in a random subcohort of 499 men (mean age 76 years) using the Southern blot. Age-adjusted mean LTL in the 5 midlife alcohol consumption groups were 8.33, 8.24, 8.12, 8.13, and 7.87 kilobases, respectively (P < 0.001). The respective proportions (%) for short telomeres were 11.24, 11.52, 11.89, 12.08, and 13.47 (P = 0.004). The differences remained after further adjustments (ever smoking, body mass index, cholesterol, perceived fitness) for LTL (P = 0.03) and tended to remain for proportion of short telomeres (P = 0.07). Neither LTL, nor proportion of short telomeres, were associated with contemporary alcohol consumption groups in old age. Even minor alcohol consumption in midlife was significantly associated with shorter telomere length in old age. The differences represent an up to 10 year gap in biological age between zero and highest consumption.