Unhealthy alcohol drinking patterns may go hand-in-hand with unhealthy eating habits, according to a new study by researchers at the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health (NIH), and the U.S. Department of Agriculture (USDA). Examining diet quality of individuals who drink any kind of alcoholic beverage, researchers found that people who drink the largest quantities of alcohol - even infrequently - have the poorest quality diets. Conversely, people who drink the least amount of alcohol - regardless of drinking frequency - have the best quality diets. A report of the findings appears in the February 15, 2006 issue of the American Journal of Epidemiology.

"This is a very useful finding that refines our understanding of the relationship between patterns of alcohol consumption and other aspects of health behavior," notes NIAAA Director Ting-Kai Li, M.D.

Previous studies have shown that moderate alcohol consumption is associated with a reduced risk for cardiovascular disease and death, notes first author Rosalind A. Breslow, Ph.D., an epidemiologist in NIAAA's Division of Epidemiology and Prevention Research. However, diet could be partly responsible for these findings, since a healthy diet has been associated with the same outcome.

"Clarifying the relationship between alcohol consumption and diet quality is an important step in determining the extent to which diet influences studies of alcohol and cardiovascular outcomes," explains Dr. Breslow. To that end, the purpose of our study was to determine the association between drinking patterns and diet quality in the U.S. population. It's important to note that determining the cause or causes of any such association was not part of our current study."

Dr. Breslow and her colleagues analyzed data collected from more than 3,000 participants in the National Health and Nutrition Examination Survey (NHANES), an ongoing survey of representative cross-sectional samples of the U.S. population conducted by the U.S. Department of Health and Human Services' Centers for Disease Control and Prevention. Data included alcohol consumption information as well as Healthy Eating Index (HEI) scores, a widely used measure of total diet quality. Created by the USDA, the HEI measures how closely an individual's diet conforms to USDA recommendations regarding vegetables, fruit, grains, meat, and milk as well as total fat, cholesterol, and sodium consumption.

Total alcohol - the sum of individuals' wine, beer, and liquor consumption -- was characterized by three variables: the amount consumed on drinking days (quantity); how often consumption occurs (frequency); and average daily volume (quantity multiplied by frequency). As alcohol quantity increased, HEI scores declined. As alcohol frequency increased, HEI scores improved. Diet quality was poorest among the highest quantity, least frequent drinkers and best among the lowest quantity, more frequent drinkers.

The researchers also found that HEI scores were not significantly different between those who drank the highest average daily volume compared with those who drank the lowest average daily volume. They therefore suggest that alcohol drinking patterns -- as measured by quantity and frequency -- rather than average alcohol consumption, should be considered in future studies of the relationship between alcohol consumption and health outcomes.

"In our study, healthier diets were associated with healthier drinking patterns," says Dr. Breslow. "In that regard, I think it's important that women have not more than 1 drink per day and that men have not more than 2 drinks per day -- the alcohol consumption recommendations set forth in the sixth edition of Dietary Guidelines for Americans, the federal government's science-based advice to promote health and reduce risk of chronic diseases through nutrition and physical activity."