Binge-watching with ads leads to binge-noshing crap.

A new study from Cancer Research UK finds that teenagers who watched more than three hours of commercial TV a day scarfed down 500 more unhealthy snacks over the course of a year than their coeds who tuned into fewer ads.

The team surveyed 3,348 young people ages 11 to 19 in the U.K. about their viewing and eating habits in the biggest study of TV streaming and diet in the country to date. The teens engaging in screen time without ads showed no increased likelihood of eating more junk food. But those who watched shows with advertisements ate hundreds of extra chips, cookies and sweetened carbonated drinks. Teens who said they regularly streamed TV shows with ads were more than twice as likely (139%) to drink carbonated drinks like soda, and 65% more likely to eat packaged and processed “ready meals,” which are often less healthy than fresh, whole foods.

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The results suggest that exposure to commercials - 60% of which the Obesity Health Alliance recently reported advertise unhealthy food and drinks - are driving younger viewers to crave and consume more junk food.

"This is the strongest evidence yet that junk food adverts could increase how much teens choose to eat,” said lead author Dr. Jyotsna Vohra from Cancer Research UK in a statement. “We're not claiming that every teenager who watches commercial TV will gorge on junk food, but this research suggests there is a strong association between advertisements and eating habits.”

"Our report suggests that reducing junk food TV marketing could help to halt the obesity crisis," she added.

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This backs previous research that has found that children who watch more than three hours of television a day are 50% more likely to be obese than the kids who are couch potatoes for two hours a day or less. Besides being more sedentary, they’re consuming food ads, which make up 50% of all the commercial time on children’s shows. And they’re not selling fruits and veggies; 34% are for candy and snacks, 28% are hawking cereal and 10% are teasing fast food.

So about 9 million children and adolescents (17% of them) are overweight -- triple the number from 1970 -- and 80% of overweight teens grow into obese adults. That puts them at greater risk of heart disease, Type 2 diabetes and cancer.

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This unhealthy snacking could also take a bite out of their future paychecks, as obese workers have a harder time getting hired and earn less than slimmer employees. And women are more stigmatized more for carrying extra weight than their male colleagues, even when their weight is still within a healthy BMI range. A 2010 study found that “very heavy” women banked $19,000 less than their peers of “average weight,” while “very thin” women earned a dramatic $22,000 more per year. And gaining 25 pounds was linked to losing $14,000 in salary per year.