Your mom’s advice was right: Put on a sweater. New research indicates that, yes, being warm helps protect against getting a cold. The body does not utilize its immune system as well at lower temperatures according to early studies. This research, being done at Yale on mice, indicates that low temperatures suppress cells’ ability to detect oncoming viruses as well as their ability to warn the immune system. This gives viruses more freedom to replicate — making you sicker!
For the mice kept at a normal, human-body temperature, they were able to fight off the virus easier than those in the cooler temps. Essentially turning the alarm signal of the body off, the virus grew until it became what we know as “the common cold.” Time to bundle up!