Fewer colds if you rate yourself healthy
Listening to your body could offer insights into the health of your immune system, suggests a study in Psychosomatic Medicine.
People who rated their overall health as excellent were less likely to become sick after being exposed to a cold virus than those with poorer self-rated health, the study found. A history of having colds was unrelated to illness susceptibility.
Poor self-rated health could be a marker for immunocompetence, or the capacity of a person’s immune system to resist disease, the researchers said. It may be possible to detect physical sensations that are actually symptoms of low-grade infections or other diseases, they suggest.
Previous studies have associated poorer self-rated health with higher white blood cell counts, a marker for infection, and inflammatory proteins called cytokines, the researchers said.
The latest study, at Carnegie Mellon University in Pittsburgh, used data from 360 volunteers, age 18 to 55 years old, who participated in two viral-challenge studies between 2000 and 2011. Over a two-week period, the subjects underwent physical exams and blood tests, personality evaluations, and daily assessments of exercise, sleep and other health-related practices. Twenty percent rated their health as excellent, 53% as very good, 25% as good, and 2% as fair.
The subjects were quarantined for six days and then given nasal drops containing rhinovirus type 39, which can cause a cold-like illness, the researchers said. The subjects’ cold symptoms were monitored for five days.
A third of the participants met the criteria for a clinical head cold, including a significant increase in nasal mucus, congestion and antibodies to cold viruses compared with pre-study levels.
Subjects reporting fair to good health were more than twice as likely to develop a cold as those with excellent self-reported health, the adjusted results showed.
Smoking and a high body-mass index were related to poor health assessments but didn’t affect the association between self-rated health and susceptibility to colds, the researchers said. Self-rated health and colds were also unrelated to rhinovirus antibody levels before the viral challenge.
Caveat: The subjects’ history of allergy wasn’t assessed and could influence their self-rated health and immunity, the researchers said.