By 
It’s been a rough fortnight. An argument with your sister, tension at work, a few sleepless nights. Then a friend wraps you in a long, tight hug, and for a moment everything feels a bit lighter.
That hug may have done more than make you feel better. Research suggests it could also help your body fight off a cold, especially during stressful times.
Volunteers who caught a cold on purpose
Psychologist Sheldon Cohen of Carnegie Mellon University has spent decades studying how stress and relationships affect our health. One of his best-known methods is direct: give healthy volunteers a cold virus and watch what happens.
In a study published in 2015 in Psychological Science, Cohen and his colleagues recruited 404 healthy adults. Each person first filled out a questionnaire about how much social support they felt they had.
Then, for 14 evenings in a row, researchers phoned each participant. They asked about any conflicts or tension with other people that day, and how many hugs they had received.
Into quarantine
After those two weeks, participants were deliberately exposed to a virus that causes the common cold, given as nose drops. They were then kept in quarantine and monitored closely for infection and signs of illness, such as mucus production and congestion.
Earlier research by Cohen had already shown that people dealing with ongoing conflicts with others are more likely to get sick when exposed to a cold virus. This time, the team wanted to know whether social support, and hugs in particular, could protect against that effect.
Hugs as a buffer
The results showed that people who felt strongly supported were protected against the rise in infection risk that came with frequent conflict. Hugging showed a similar protective effect. In fact, hugs accounted for about a third of the protection that social support provided.
The key word is stress. The benefit of hugs was clearest for people dealing with frequent conflicts, the group most at risk of getting sick. As Cohen put it, support from people in your life may matter most in times of stress and conflict.
Milder colds too
There was a second finding. Among people who did become infected, those who received more frequent hugs had less severe illness symptoms, whether or not they had been dealing with conflict.
Cohen summed it up simply: those who receive more hugs are somewhat more protected from infection.
What hugs might do inside the body
The study didn’t measure what was happening in participants’ brains or bodies, but scientists have some ideas about how hugs could help.
Stress activates the body’s HPA axis, a chain of signals from the hypothalamus to the pituitary gland to the adrenal glands, ending with the release of cortisol. Over time, high stress can weaken the immune system’s ability to fight infection.
Warm physical contact may help calm that system. Hugs and other affectionate touch are linked to the release of oxytocin, a hormone involved in bonding that may help dampen stress responses.
Our skin is also wired to notice affectionate touch. Some nerve fibers respond best to slow, gentle stroking, and send signals to the insula, a brain region involved in emotion and body awareness. This may help explain why a hug can feel calming almost instantly.
Cohen’s team suggested the benefit could come from the physical contact itself, or from what a hug represents, a sign that someone cares about you and has your back.
Not a cure
The study had limits, and not everyone was convinced. The statistics were complex. Touch researcher Tiffany Field told one newspaper she saw little evidence that hugging itself protected against infection.
The study also showed a link rather than proof that hugs prevent colds. People who get more hugs may differ in other ways, such as having closer relationships or healthier routines.
Still, the findings fit a large body of research showing that close relationships are good for our health. Hugs won’t replace hand-washing or sleep during cold season. But on a stressful day, a hug from someone you trust may do a little more good than you’d think.
