Whether it’s Gwyneth Paltrow promoting waste-of-time-and-money food-sensitivity testing, or Katie Couric instilling unwarranted fears about the safety of HPV vaccines, or Dr. Mehmet Oz telling 4 million TV viewers that a discredited supplement offers a “magic” and “revolutionary” way of losing weight, celebrities are constantly (it seems) trying to advise us about medical matters.
And all too often, we follow that advice without doing any critical thinking first.
“Celebrities have crept into our medicine cabinets and kitchens, influencing what pills we pop, tests we order and foods we fear,” write science journalist Julia Belluz and McMaster University epidemiologist Steven J. Hoffman in a commentary published Wednesday in the Los Angeles Times. “More often than not, their advice and products are dubious.”
So, why do we believe celebrities on such an all-important matter: our health?
A systematic review
To answer that question, Hoffman decided to conduct a systematic review of research on celebrity. He drew on studies in economics, marketing, psychology and sociology. The search revealed, he says, several “compelling narratives” about why so many of us let ourselves be influenced by celebrities when making important health decisions for ourselves or for our families.
Hoffmann published his findings in the Dec. 18 issue of the BMJ. Here’s a quick summary of some of those findings:
- Celebrity endorsements tend to trigger what is known in economics as herd behavior. Such behavior can be benign when people are herding to buy a particular brand of shoe or toothpaste. But in medicine, such behavior can — and does — lead to unnecessary and potentially harmful medical diagnoses and treatment.
“For example,” writes Hoffman, “Angelina Jolie’s preventive double mastectomy after testing positive for the BRCA1 gene mutation led to a heightened interest in genetic testing. However, since BRCA mutations are rare, testing is only recommended for women with a high risk or family history of breast cancer. Jolie’s announcement may have catalyzed a herd seeking the test, including many for whom it is neither appropriate nor cost effective.”
- As marketing experts know quite well, fame gives many celebrities a “halo” of credibility and trustworthiness that often extends into areas in which they have no training or expertise. In fact, celebrities can be perceived as having more credibility than their non-celebrity counterparts, such as doctors, writes Hoffman.
We also want to emulate celebrities we like. Thus, we try to acquire products (or ideas) associated with those celebrities.
“Tobacco companies are infamous for using celebrities to sell their products,” writes Hoffman. “Through fostering close relations with movie studios and prominently featuring stars in advertisements, companies transfer the attractive and sophisticated image of celebrities to their cigarettes. The strategy works: Smoking in movies has been found to alter perceptions of and susceptibilities towards smoking among adolescents.”
- From psychology’s theory of cognitive dissonance comes an explanation for why we follow a favorite celebrity’s medical advice even if we recognize that the advice is on shaky medical ground. We do it because not following the dubious advice makes us feel even more uncomfortable by conflicting with our “adoration for the celebrity,” says Hoffman.
A powerful halo
“It seems that we as humans are biologically, psychologically and socially hard-wired to trust celebrities’ health advice,” says Hoffman in a video produced by BMJ to accompany the study. “That halo that glows from celebrities is so powerful that we just can’t resist following whatever they say.”
But, of course, we need to resist — and encourage others to do so, too. Our health may depend on it.
“While celebrities sometimes encourage healthy behaviors of proven benefit, at other times they spread misinformation and harmful practices,” writes Hoffman. “The potential years of life lost and wasted healthcare dollars from all the useless products and bogus treatment that celebrities sometimes promote at the expense of evidence based practices, make this phenomenon a critical challenge worthy of serious address.”