Common sense tells us that a hug is good for us. Now a new study confirms just how and why hugs are so beneficial.

A study of 404 healthy adults by experimenters at Carnegie Mellon University examined the effects of hugs on the health of participants, particularly their susceptibility to developing the common cold. People who reported more hugs and greater social support were 32% less likely to come down with a cold, and the researchers interpreted that a “stress-buffering” effect of hugging explained the beneficial effect.

“Hugging protects people who are under stress from the increased risk for colds,” notes study lead author Sheldon Cohen, a professor of psychology at Carnegie Mellon University in Pennsylvania. Cohen called hugging “a marker of intimacy and helps generate the feeling that others are there to help in the face of adversity.”

There is, in fact, a scientific basis for Cohen’s view on the effects of hugging. Some experts attribute the stress-reducing benefits of hugging to the release of oxytocin in the body. They refer to oxytocin as “the bonding hormone” because it promotes attachment in relationships, especially between mothers and their newborn babies.

Classic research on attachment between mothers and babies was done years ago by psychologists such as Harlow in America and Spitz in London. Harlow experimented with baby monkeys and maternal deprivation and found that monkeys needed physical contact with their mothers more than they needed milk. When they didn’t get that attachment with their mothers, they suffered from depression and a host of other emotional disorders. Spitz studied babies in a foundling hospital in London during World War II and found that orphans who had lost their mothers during bombing raids by the Germans quickly deteriorated when they didn’t get the physical comfort they needed. About 33% of these babies stopped eating and died.

It sounds simple; just get a hug a day and you’ll be releasing oxytocin all over the place and you’ll enjoy steady health. The catch is that the above study was done with healthy adults–presumably adults who did not suffer from a major emotional disorder. But what happens if you are unhealthy?

People who suffer from major depression, for example, eschew physical contact. They don’t want to be touched and they don’t want to touch anybody. Harlow found in his studies with monkeys that if they did not establish a firm attachment with their mothers during a critical period of infancy, they would have a difficult time establishing an attachment later on. Indeed, they would have an attachment phobia.

For such people a hug a day would likely diminish their depression as well as make them less vulnerable to not only illnesses such as colds but also the whole spectrum of illnesses. However, getting them to accept hugs or bonding with another human being is the resistance that must be overcome. Overcoming this resistance to attachment is the main task of psychotherapy with such individuals and often takes years to accomplish.

Indeed, resistance to attachment (some call it fear of intimacy) may well be the primary resistance to therapy and to any relationship. Physical comfort is at the core of this resistance. A person who didn’t receive this in early childhood, or received it improperly (as inappropriate sexual touching) is often disgusted by it as an adult. Hugging seems like such a simple thing, but is actually very complex.

Still, this research is valuable because it confirms what we already knew, as research often does, and provides a rationale for encouraging people who seek out hugs in times of stress, if they don’t do so already. If you are stressed about your spouse, about a job interview, a final exam, or any kind of difficult situation, get a hug.

Nevermind the apples. Hugs are much more likely than apples to circumvent a doctor’s visit.