Alcohol dependence is determined by many different factors, both biological and environmental. Though science has yet to drill it down to a specific gene, researchers are certain that alcoholism has a genetic influence that predisposes certain people to be at risk for alcohol dependence.

Alcohol consumption patterns are also influenced by environmental factors. Recent research by Rosenquist and colleagues (2010) examines patterns of drinking among social networks. Peer influence can be powerful, and the researchers wanted to see how effective it is in deciding who drinks, and who doesn’t.

The study looked at 5,124 members of the offspring cohort of the Framingham Heart Study, which collected 7 waves of data between 1972 and 2000. The participants’ family members, friends, neighbors and coworkers were identified at each wave of the study. Only the contacts that were involved in the Framingham Heart Study were included in this study.

The participants reported their alcohol use during each wave of interviews. The responses enabled the researchers to organize the participants into groups based on alcohol consumption.

The results of the study showed that the individuals’ drinking patterns varied according to the behavior of the social network around them. The results were consistent up to three degrees of separation (i.e., friends’ drinking, friends of friends’ drinking and friends of friends of friends’ drinking behavior). Geographical distant had no impact on the results.

The study also revealed that having a social network in which there was a high level of heavy drinkers predicted that there would be an increase in the individual’s drinking by the next wave of interviewing. In addition, a high level of abstainers predicted a decrease in the individual’s drinking by the next wave of interviewing.

There were different levels of influence, based on the role that a member of social networks played in the life of the individual. For instance, friends and spouses (and in particular, female friends and wives) had the strongest influence on future alcohol consumption. Conversely, neighbors and coworkers were not found to have any influence at all.

The study’s findings are potentially limited because only FHS contacts were used, and participants’ social contacts not involved in FHS may have had significant influence over their drinking behavior. Alcohol consumption information was also self-reported. Also, the influence of drinking behavior on the individual’s social network was not examined.

The findings of the study are significant because they expose the important role that social networks have in influencing alcohol consumption patterns. They indicate that alcohol consumption may be socially contagious.