Watch any football, hockey, or baseball game and you will see some of the most physically fit people on the planet — along with advertisements for sugary sodas, pizza, candy, and chips.

In fact, researchers at the New York University School of Medicine have determined that the majority of the food and drinks marketed on television and online during sporting events are unhealthy and may contribute to children's expanding waistlines.

Poor diet has long been known to be a driver of childhood obesity, and it has also been demonstrated that advertising on TV shows aimed at kids can influence youngsters' food preferences.

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But these researchers said they were astonished at the ads they tallied during programs showcasing athletics.

"It turned out to be that unhealthy food and beverages were dominant in the sponsorships by a landslide," said Marie Bragg, the lead investigator of the study.

The results of the study, which was funded by the Robert Wood Johnson Foundation, were published Monday in the journal Pediatrics.

Bragg was struck by the contrast between extremely fit athletes and commercials promoting sugary, fatty, salty treats.

"The mixed message that is sent out by the sponsorships is what motivated us," she said.

While sports programming does not specifically target children, kids under 12 are a large part of the audience.

Researchers looked at 2015 Nielsen audience data to select the 10 sports organizations watched most by children ages 2 to 17 years and determine which had the highest number of food and/or nonalcoholic beverage sponsors. The National Football League led the list with 10 sponsors, the National Hockey League had seven, and Little League baseball came in third with six sponsorships.

They also found that in 2015, youths watched telecasts associated with those 10 sports organizations more than 412 million times.

The researchers then assessed the products advertised by the sponsors for nutritional value using a nutrient profile model from the United Kingdom and Australia – the United States does not have a comparable measurement system. Researchers found most of the foods and beverages were rated as unhealthy.

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Since social media is so popular with teenagers, researchers then looked at YouTube ads from the sponsors that were promoting the products to see how many views those commercials had between 2006 and 2016. One limitation of the study was that there was no way to determine the age of the YouTube viewer or whether it was a unique or repeated view, Bragg said.

The big surprise in the study was that Little League was ranked third for unhealthy food and nonalcoholic beverage sponsors, said Bragg.

The authors recommended that sports organizations develop more health-conscious policies and ban ads from companies that are promoting unhealthy products or limit the ads to only their healthiest items. They also suggest that grassroots efforts and accompanying media attention could convince corporations to change their marketing practices.

Bragg pointed to successful examples of healthy changes, such as the ban on televised tobacco ads and General Mills' decision to reduce the amount of sugar in cereals.