This chapter discusses the effect of alcohol on eye diseases. Although alcoholics and people using three drinks of alcoholic beverages per day have increased risk of cataract and aging diseases of the eye, moderate consumption of alcohol appears to reduce risk of these diseases. The risk of cataracts shows a J-shaped response to consumption of alcoholic beverages, typical of hormesis. These effects on aging diseases of the eye may be a proxy for aging in general, because several studies have shown that early cataract operations are predictive of premature death. The well-known association of oxidative damage with aging is consistent with numerous reports indicating that alcoholism or hard drinking are reported to cause similar oxidative damage. In the case of heavy alcohol use, the oxidative damage to the liver appears to be a major factor in liver necrosis and this oxidative stress is likely to cataract formation. Damage to mitochondria may be involved in the pathogenesis of both these disease processes. Studies suggest that, the plasma has increased antioxidant activity after one drink but becomes pro-oxidant after three drinks, consistent with the epidemiological observations of decreased risk for moderate drinking and increased risk after three drinks.