Food companies have ramped up spending on TV commercials targeting black consumers while cutting back overall spending on advertising, according to a new study.

During a five-year period when both total and Spanish-language TV advertising by food companies fell 4 percent, TV marketing aimed at black Americans spiked more than 50 percent, according to a report from University of Connecticut's Rudd Center for Food Policy & Obesity.

Black teenagers saw more than twice as many ads for unhealthy foods compared to white teens in 2017, the study found.

Both fast-food chains and packaged-food companies increased their spending for the demographic group during the period from 2013 to 2017.

PepsiCo Inc.'s spending on TV commercials targeting black shoppers rose by 37 percent, while Taco Bell owner, Yum Brands Inc.'s rose 31 percent, according to the study. The companies did not reply to a request for comment.

As food companies and restaurants fight to win over U.S. consumers, ads targeting young people and minority members have come under scrutiny and been linked to rising obesity rates.

The obesity rate for U.S. children has risen across the nation and now stands about 18.5 percent. It's higher for black and Latino children, according to the Centers for Disease Control and Prevention.

Jennifer Harris, lead author of the study and director of marketing initiatives at the Rudd Center, said of food companies: "They're really focusing on products that can harm kids' health, and they're focusing on black networks. Given higher rates of obesity, diabetes and hypertension in black families, they're basically contributing to those diseases."

Hershey Co. was the only large advertiser to reduce spending that targeted black consumers, the study found.

"Hershey does not buy TV media based on ethnic targeting," spokesman Jeff Beckman said in an e-mail.

In 2010, then-First Lady Michelle Obama launched the Let's Move campaign, with the goal of lowering the U.S. rate of childhood obesity to 5 percent by 2030. At the time, the campaign highlighted food and beverage companies as "key actors" in preventing obesity.

The study analyzed television marketing data from the 32 companies responsible for most food advertising in 2017. It analyzed channels with a target audience of black Americans, including BET and VH1.

Patton and Holman write for Bloomberg.