Do you know what causes the common cold? If you thought: "a virus" - you are partially correct. A variety of viruses are responsible for those sneezy, achy, scratchy-throated illnesses-critters like rhinoviruses (I imagine them with large horns), coronaviruses, RSV, and adenoviruses. But a virus, alone, will not cause you to experience cold symptoms, especially if your immune system can thwack it into submission before it gains a foothold in your nose, throat, or other susceptible tissues.
That is why people whose immune systems are temporarily or permanently weakened can be susceptible to colds. Consider chronic stress. Ask a group of college students about their emotional lives and those who report higher levels of stress will be more susceptible to cold symptoms. We know that because researchers have exposed healthy college students to cold viruses after assessing their stress levels and followed up to measure their cold symptoms.
People who are chronically stressed are sick more often than their lesser-stressed peers. Indeed, the stress people experience-from socioeconomic struggles, family dysfunction, sexism, and racism -increase their susceptibility to illness.
On the flipside, a wide range of personality traits reduce the rate of illnesses. For instance, people who are usually in good moods, have high self-esteem, and rate high on "self acceptance" are less susceptible to the common cold.
Or so we used to think! Consider a cold virus study led by Cameron Wiley from UC Irvine (but now at Harvard School of Public Health). Like many such studies, researchers exposed healthy volunteers to cold viruses and tracked their symptoms. Prior to the exposure, participants responded to a survey about a range of personality and emotion variables.
For European-Americans, the expected pattern emerged: good mood, high self-esteem, and high self-acceptance - all these traits predicted a lower likelihood of getting a cold.
But for African-Americans? The pattern did not hold. Take this picture of the relationship between self-esteem and cold symptoms. Among European Americans: lower self-esteem was associated with more cold symptoms. Among African-Americans, the opposite pattern held: higher self-esteem predicted more cold symptoms:
The researchers offer a few possible explanations for this finding.
Emotion and personality measures might work differently across populations. In African-Americans, people's survey responses might "serve as a byproduct of emotional suppression or the desire to present themselves" in socially acceptable ways. An African-American woman, forced to live in a socially expected "superwoman" schema, might report low amount of anger because she is socially expected to control such feelings. Wiley communicated another example to me: "An African American man, expected to exemplify 'John Henryism' by showing continued strength and resilience in the face of any hardship, might not have the capacity to accurately report positive emotions."
In addition, African-Americans may experience and/or report high levels of positive emotion as a way of coping with frequent experiences of discrimination. Thus, high self-report of positive emotion might serve, counterintuitively, as a marker of the kind of stress that weakens people's immune systems.
I am realistic about our society's ability to convince all Americans that racism, structural or other, not only exists but has an enormous impact on people's lives. Experiencing an occasional cold is one of the least such impacts. But rigorous studies like this should lend more credibility to these claims.
If you, like me, regularly shrug off common colds, don't just consider yourself lucky. Consider yourself privileged!