Even moderate alcohol use affects cognitive function. Moderate and heavy drinking of alcohol negatively affects brain structure and word fluency, and even light drinking has no protective cognitive effects, reports a study of 550 men and women followed for 30 years. Magnetic resonance imaging scans showed reduced size of the hippocampus and reduced white and gray matter in those who drank the most alcohol. Hippocampal atrophy was also higher in moderate drinkers compared with nondrinkers. Heavy drinkers performed worse in word fluency tests than nondrinkers, but word recall was not affected by alcohol use. Drinking habits of participants changed little over the 30-year study. "Alcohol might represent a modifiable risk factor for cognitive impairment, and primary prevention interventions targeted to later life could be too late," write the researchers in the June 6 British Medical Journal.