Milk Life, a campaign from the MilkPEP board (which is funded by U.S. milk companies), made its Olympic debut in the 2016 Summer Olympics in Rio. Ahead of the PyeongChang 2018 Olympic Winter Games, the board said the campaign would make a splash again—securing a partnership with the U.S. Olympic Committee to produce content around the games though the 2020 Summer Paralympic Games in Tokyo.

What the board likely didn’t know was that a counter group comprised of former Olympians were devising a plan to drop a public service announcement during the closing ceremonies in PyeongChang urging their fellow athletes to drop milk and switch to a plant-based diet.

The below spot, part of a larger “Switch4Good” campaign, will air regionally in six markets (New York, Los Angeles, Chicago, Washington D.C., San Francisco and Dallas) during the start of the closing ceremony in PyeongChang and features stories from five former Olympians about the benefits they experienced when they switched to a vegan diet.

The campaign is led by Dotsie Bausch, a silver medal-winning cyclist, and features Seba Johnson, the first black female skier in the Olympics and the youngest in her sport at the 1988 games; Kendrick Farris, a three-time Olympian and the only U.S. male weightlifter to qualify for the Rio games; Kara Lang, a member of the 2008 U.S. women’s Olympic soccer team; and Malachi Davis, a 2004 Olympic sprinter.

“I switched to a whole foods, plant-based diet about two and a half years before the 2012 Olympic games,” Bausch told Adweek. “I stood on the podium at 39 years old, the oldest competitor ever in my specific discipline. My diet change was the key factor in me being able to recover quicker, decrease inflammation and have all the stamina and energy I needed to compete against competitors 20 years my junior.”

Bausch said she decided to take her story to a broader audience to correct what she sees as false advertisement from milk companies. According to her, drinking two glasses of milk a day (the recommended dose) increases women’s risk of fracturing a hip by 45 percent, and women who drink just one glass of milk daily are three times more likely to get ovarian cancer.

For her, going vegan changed her life.

“My physical body became like a machine,” Bausch described of herself after she made the dietary switch. “I went from being able to lift 300 pounds on the inverted leg sled to lifting 580 pounds times 60 reps times five sets.”

She added: “The biggest misconception around milk is that we need it for calcium for strong bones. Dark leafy greens, for example, have more bio-available calcium than milk does.”

Bausch said the closing ceremony for the PyeongChang games was the perfect medium to debut her “Switch4Good” campaign, given that it will shake up what viewers have been seeing from the Milk Life ads throughout the winter programming, specifically its claim that “nine out of 10 Olympians grew up drinking milk.”

“Which is probably true,” Bausch noted, “but also wildly misleading. Our grandparents grew up smoking. I bet nine out of 10 serial killers grew up drinking milk, too. What you drink as a child has nothing to do with whether you will grow up and become an Olympian.”

The 30-second spot, produced by creative shops Effect Partners and Pollution.tv, was handled by Oscar-award winning director Louie Psihoyos, who is also the visionary behind The Cove, a 2009 documentary that shed light on questionable dolphin hunting practices in Japan.

After its initial airing, the spot will run during late-night news and Prime Encore on Sunday in nine markets: New York, Los Angeles, Chicago, Philadelphia, Washington D.C., Boston, San Francisco, San Diego and Miami. The “Switch4Good” campaign is also supported across social media.

While people who describe themselves as vegan make up a small sliver of the total U.S. population (6 percent in 2017, according to a study by ReportBuyer), the trend is gaining prominence among younger consumers—those that milk companies have been having trouble reaching. In 2014, only 1 percent of the U.S. population was vegan, according to the ReportBuyer study.