Childhood obesity has more than tripled in the last 30 years, and its causes appear to be a complex mix of genetic, behavioral, and environmental factors. Many assume that the consumption patterns and marketing relating to sugary drinks —  a well-known target in recent years for those campaigning to end childhood obesity — might have changed because of sustained scrutiny.

A 2011 report by the Yale Rudd Center for Food Policy and Obesity, “Evaluating Sugary Drink Nutrition and Marketing to Youth,” examines nutrition and marketing data on sugary drinks to evaluate the claim that the consumption and marketing of these products is harmful to children and adolescents.

The researchers analyzed the nutritional content of more than 600 drinks with added sugar, including soda, fruit drinks, energy drinks, sports drinks, iced tea, and enhanced water, as well as diet energy drinks and diet children’s fruit drinks. They then looked at data from Nielsen, comScore, Arbitron, SymphonyIRI, and their own studies to examine the marketing of these products to youth, paying special attention to black and Hispanic youth where data was available.

Key results include:

• Spending on marketing for regular soda, energy drinks, and fruit drinks increased by roughly one third between 2008 and 2010, while on average spending increased 5% during that period for all drinks studied.
• Between 2008 and 2010, total exposure to sugary drink advertising increased 4% for preschoolers, 8% for children, and 18% for teens. TV advertising in particular is on the rise for regular soda, energy drinks, and iced tea; children and teens viewed twice as many TV ads for regular soda in 2010 as they did in 2008.
• Sales of regular sodas were double their diet counterparts, and full-calorie energy drinks sold five to six times as much as the reduced-calorie varieties. Spending on marketing of non-diet varieties similarly dwarfed marketing of diet varieties.
• Full-calorie sodas, fruit drinks, and energy drinks had the most sugar, with 45 grams in a 12-ounce can and 75 grams in a 20-ounce bottle — about twice the recommended daily allowance; flavored water, sports drinks, and iced tea typically contained about half as much.
• Labeling on products appeared to deliberately disguise their poor nutritional value, and nutrition information was often missing and/or hard to find and understand.
• Even though they watched fewer hours of TV, teens viewed 12% more ads on TV for all sugar drinks and energy drinks compared to adults.
• Sugary drink brands advertised aggressively on the Internet, Including social media and mobile devices, and used promotions, sponsorships, and other youth-oriented techniques.
• Sugary drink and energy drink brands target African-American and Hispanic youth disproportionately compared to white youth, and contain messages likely to appeal to them specifically.

The researchers conclude by recommending that beverage companies provide better products, improve labeling, and reduce marketing directed at children.