Green (Living) Review: common cold

Sick with a cold, blowing nose Once again, your grandma was right (you eat your vegetables, right?). She might just have said "it's cold outside, you'll catch a cold" while the recent study published in theProceedings of the National Academy of Sciences phrases it a bit differently ("Temperature-dependent innate defense against the common cold virus limits viral replication at warm temperature in mouse airway cells"), but the general idea is the same.

Rhinovirus, which is the most frequent cause of the common cold and "asthma exacerbations", can reproduce better at the lower temperatures found in a nose cavity compared to the warmer temperature found in lungs. It appears that this is because the body's immune system is less effective at cooler temperatures, thus giving the virus more leeway to get a toehold and, eventually, overrun our system.

hugging The tongue-in-cheek name of this publication might imply that we are already pro-hugging, but new research suggests that hugs may have preventative health benefits.

Affectionate physical contact, and the social support that comes with it, has previously been shown to make us feel good and reduce stress. We also know that being stressed out makes us more prone to getting sick. So, researchers from Carnegie Mellon University set out to see if people who hug frequently are more resistant to the common cold.

They also wanted to see if perceived social support—if people feel supported by their friends and families—is correlated with better resistance to infection.

The researchers surveyed 404 healthy adults about their frequency of hugs and about how much social support they feel in their lives. The participants were then deliberately exposed to the common cold virus, and monitored in quarantine.

Both participants who felt more social support and those who received frequent hugs experienced fewer cold symptoms.