Researchers have been swabbing noses with cold viruses for years, discovering that certain lifestyle factors -- such as lack of sleep and stress -- makes a person more susceptible to developing a runny nose, hacking cough, and all-over achy feeling. Now, though, a new study lays out a plausible explanation for why those under chronic stress are likely to get more frequent colds: The body’s reaction to the stress hormone cortisol becomes impaired when stress is prolonged, making cortisol unable to turn down the immune reaction that causes cold symptoms.
In the study published Monday in the Proceedings of the National Academy of Sciences, researchers asked 276 volunteers detailed questions to determine if they were under chronic stress due to, say, unemployment, marriage troubles, or being a full-time caregiver to a sick loved one. They found those who scored high on the chronic stress scale were more likely to have severe cold symptoms after being infected with a virus compared to those who scored low on the scale. Stressed-out folks also had higher levels of inflammatory chemicals that indicated their bodies had developed a resistance to cortisol.