The conflict between the dairy industry and plant-based brands heated up this year when the Food and Drug Administration ruled that the latter could call themselves milk. Following that decision, MilkPEP (short for Milk Processor Education Program) ran a campaign that garnered attention for its star–Aubrey Plaza–mocking the plant-based sector and arguing “only dairy milk is real milk.”

Now oat drink Oatly is firing back by touting its sustainability and challenging the dairy industry to show its carbon footprint.

Oatly is taking out full-page ads in the Sunday, May 7 issues of The New York Times, Los Angeles Times and Washington Post and installing billboards in Times Square and Hollywood Boulevard on May 8. Each ad shows a package of Oatly, noting that it takes the equivalent of .62 kg of carbon dioxide to produce. In a gesture of transparency, Oatly will be sharing the climate footprint on packages for several of its products in the U.S. and offers a full list at oatly.com/footprint.

The other part of the campaign challenges the dairy industry to reveal their own carbon footprint by answering 68 questions. Oatly has offered to pay for ad space for the brands if they agree.

A March 6 post on Oatly’s blog boasts that according to a 2022 life cycle assessment, oat milk has a 44% to 76% lower climate impact than cow’s milk across six markets. 

“The ultimate goal of our campaign is to advocate for transparency on the impact products have on the planet so consumers can make more informed purchases,” Oatly executive director of brand and creative, Armando Turco, told Adweek.

A recent poll released by Oatly shows that 54% of Gen Z and 49% of millennials prefer plant-based milk to cow’s milk.

The brand has also pledged to reduce its climate footprint per liter of product produced by 70% before 2029.