What do football great Peyton Manning, basketball icon LeBron James and tennis dynamo Serena Williams have in common?
They are superstar athletes who send super-sized mixed messages to children about diet and healthy eating by endorsing junk food, according to a new study published Monday in the journal Pediatrics.
Researchers deemed the trio "the highest contributors to the marketing of unhealthy foods" among the most influential athletes in the world.
"The striking irony here is that you have some of the world's most physically fit athletes promoting really unhealthy foods," said lead author Marie Bragg, a doctoral candidate in psychology at Yale University.
Canada's Sidney Crosby was among 100 top athletes analyzed, but researchers determined that his endorsement portfolio of Tim Hortons, Gatorade and Dempster's Bread was among the healthiest, compared with those of other elite sports figures.
Athletes have been the face of everything from fast food to beer, from shaving cream to automobiles, for decades. Baseball players in particular were mainstays in cigarette advertising until the 1960s, when the tobacco industry agreed to not depict well-known athletes in advertisements.
"They help move products," said Marc Ganis, a sports image consultant. "They help create a perception of positive alignment between a consumer, the product and the pitchman."
Now, with the recognition that childhood obesity has reached epidemic proportions, the public appetite for sports figures selling the likes of soft drinks and sugary cereals seems to be waning.
In June, child-nutrition advocates slammed tennis darling Maria Sharapova over her line of sugar candy, Sugarpova, accusing her of exploiting her status to promote junk food.
Last year, the Academy of Royal Medical Colleges sounded the alarm over the London Olympics Committee selling the exclusive rights to peddle brand-name food and non-alcoholic beverages at the Games to McDonald's and Coca-Cola.
At the same time, a 2012 study from Sydney University suggested athletes are ambivalent about the topic. While 92 per cent of 2,000 elite athletes surveyed "showed a strong disinclination" to personally pitch unhealthy foods, more than half, 54 per cent, thought sports was an acceptable marketing tool for them.
"Athletes, of all people, should know better than to promote these products," said Julie Greenstein, deputy director for health-promotion policy at the Center for Science in the Public Interest in Washington. "Athletes are heroes to most children and it's a shame that they're using their bully pulpit to sell obesity."
In the Yale study, athletes were analyzed based on their prominence in their sport and the value of their endorsements. Researchers then created a weighted index on a scale of 100 that reflected the "negative marketing and nutrition impact," with the lowest scores being the most negative.
Manning, Williams and James, who are among the most recognizable athletes in the world, earned scores of 28.9, 32.4 and 42.7, respectively. Between them, they endorse Pepsi-Cola (Manning), McDonald's (James) and Oreo cookies (Williams). By contrast, Crosby earned an index score of 76.3.
The results are skewed by the athletes' influence on popular culture. For example, hoopster Chris Paul, a pitchman for McDonald's and Powerade, earned a score of 100 in part because his endorsement power carries less weight than other elite athletes.
Messages seeking comment left for Manning, Williams and James through their agents were not returned.
Four out of five of the 62 endorsed food products in the sample were deemed "energy-dense and nutrient-poor," while 93 per cent of the 46 beverages in the sample received all their calories from added sugars. Children ages 12 to 17 were found most likely to be exposed to the advertisements.
The study recommended athletes eschew lucrative endorsement deals for junk food and that countries adopt policies to restrict that type of advertising.
"Professional athletes wouldn't endorse tobacco today because it would be a liability for them," Bragg said. "We're hoping one day that the same would be true for unhealthy foods."