Hugs may be an effective way of preventing the common cold, a new study from Carnegie Mellon University (CMU) reveals.

Hugs as a means of support were found to be highly effective at preventing infections by the virus which causes the common cold. The benefit takes place in those people with immune systems weakened by stress, which can often be brought about by conflict with others. Those people who still developed colds despite frequent hugs experienced less-severe symptoms, the study revealed.

"We know that people experiencing ongoing conflicts with others are less able to fight off cold viruses. We also know that people who report having social support are partly protected from the effects of stress on psychological states, such as depression and anxiety," Sheldon Cohen from the Dietrich College of Humanities and Social Sciences at CMU, said.

A total of 404 healthy adult subjects were examined in the study, which included a self-assessment of perceived social support. Telephone surveys were conducted of each of the volunteers over the next 14 days, asking about conflicts with others, as well as the amount of social interaction subjects experienced that day. Participants were then subjected to a common cold virus, and set aside in quarantine, where their health was monitored. Researchers found that those with greater levels of  perceived social support were better able to fight off illness, despite the effects of conflict-related stress. Less severe symptoms were experienced by those with more social support, regardless of stress levels. Hugs were found to account for one-third of the benefits derived from social support.

"The apparent protective effect of hugs may be attributable to the physical contact itself or to hugging being a behavioral indicator of support and intimacy," Cohen said.

Researchers believe that hugs from loved ones may provide health benefits through reducing stress that could otherwise reduce the natural ability of immune systems to battle infections. It is also possible the advantage may be brought about through physical contact, or to increased feelings of support and intimacy among people receiving hugs. This study also lends support to the idea that hugs effectively convey feelings of support to others.

The original aim of the study was to examine the role of social support as a whole in prevention infection. It was only when hugs were found to account for 32 percent of the benefit that their primary role in health was revealed.

Although they are certainly no definite protection against colds, giving and receiving hugs may be an effective way of preventing infection by the virus.

The health benefits of hugs on preventing infection by cold viruses was detailed in the journal Psychological Science.