NEW YORK - When Miami Heat star LeBron James isn't scoring baskets, he's busy selling soft drinks, sports drinks and fast food.
But James isn't alone. In a new study, many top United States athletes, from Peyton Manning to Serena Williams, were found to be all over television promoting food and drinks, most of which aren't very healthy.
"We see these people - they've obviously (reached the top) of sports achievement, they're obviously living a healthy lifestyle - and they're endorsing these foods. And that kind of lends an aura of healthfulness to these food and beverages that they don't deserve," said Ms Emma Boyland, from the University of Liverpool in Britain.
"The message is really getting mixed up," added Ms Boyland, who studies marketing and children's food choices.
The new study was led by Ms Marie Bragg from the Rudd Center for Food Policy and Obesity at Yale University in New Haven, Connecticut.
She and her team compiled a list of advertising deals involving 100 top athletes. In 2010, those athletes endorsed a total of 512 brands. About a quarter were of food and beverages.
The athletes endorsed 62 food products, including burgers, cookies and cereal. Forty-nine of them were high in calories and low in nutritional value.
They also endorsed 46 sports drinks, soft drinks and other beverages. In 43 of those, all the calories came from added sugar, wrote the research team.
"What stood out to us was the striking irony of the practice of having the world's most physically fit athletes endorsing these products," said Ms Bragg.
Based on TV-viewing data, her team found that teens saw more of the ads by athletes during the year than adults.
Ms Boyland told Reuters Health: "We know that children and (teens) are really affected by this type of thing. We know that influences the type of food they choose and eat."
It's also clear that such selling tactics work, researchers said. The proof is that companies will pay athletes millions to endorse a product, they said.
Ms Bragg said parents should be aware that many products being marketed to children may be of questionable nutritional quality.
"Just because they're athletes doesn't mean that what they're endorsing is healthy," she told Reuters Health.