The drinking habits of the people in your extended social group play a major role in determining your own rate of alcohol consumption, says a new study.

Researchers used data from the landmark Framingham Heart Study which followed 12,067 people for more than 30 years and helped to define the patterns in social networks of other health issues such as obesity, smoking, and sexually transmitted diseases.

In this analysis, the researchers sought to explore patterns of alcohol use in a large social network.

“We've found that the influence of your friends and people you have connections with can affect your health just as much as your family history or your genetic background,” said Nicholas Christakis, professor of medicine at Harvard University and lead author of the study.

“With regard to alcohol consumption, your social network may have both positive and negative health consequences, depending on the circumstances.”

In the study, self-reported alcohol intake over time followed changes in the alcohol intake of the respondents' social contacts.

Researchers found that a person was 50 percent more likely to drink heavily if a person they are directly connected with also drinks heavily and 36 percent more likely to drink heavily if a friend of a friend drinks heavily, says a Harvard release.

The impact extended up to three degrees of separation. The researchers suggest this social phenomena could have other implications for clinical and health interventions.

Social networks could be used to exploit positive health behaviours and further support group interventions.

These findings were published in Annals of Internal Medicine.