When Danone announced last week that it has entered into an agreement to buy WhiteWave, the French dairy company touted its new acquisition target’s “plant-based milk” in the headline of the press release.
But not all of WhiteWave’s WWAV plant-based portfolio has been so rosy. Soy milk, once the juggernaut of the plant-base world, has become a laggard. According to data from industry tracker Euromonitor, WhiteWave’s Silk soy milk brand had seen its sales cut by more than half from its peak of $558 million in 2008 to $242 last year.
Meanwhile, Silk’s U.S. sales of almond milk have more than tripled between 2011 and 2015, hitting about $500 million in 2015, according to Euromonitor. Silk’s coconut milk, while a modest $45.7 million in U.S. sales in 2015, is also on an upward trajectory, growing nearly 150% since 2011.
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The shift at WhiteWave’s Silk brand reflects the broader change among alternative milks. Soy milk’s rise began in 1999 when the Food and Drug Administration ruled that food manufacturers could add health claims to labels touting the “association between soy protein and reduced risk of coronary heart disease.” That helped buoy U.S. soy milk sales, which hit a peak of $1.2 billion in 2008. But by 2015, the category had plummeted 57%.
So what happened to soy milk, the one-time go-to alternative for the lactose-intolerant and vegans?
In short, its reputation for healthiness is not what it used to be. “Concerns about the health benefits of soy amongst health professionals dampened the demand,” says Emily Balsamo, a research analyst at Euromonitor. The American Heart Association wrote a letter to the FDA in 2008 “strongly” recommending that the agency revoke the heart disease claim because “recent data are less conclusive.”
Balsamo notes that some studies have also suggested soy milk may actually increase the chance of getting breast cancer by stimulating estrogen receptors in breast cancer cells.
Meanwhile, other non-dairy milk alternatives like almond milk gained more mainstream traction, growing nearly 14-fold into a $1.4 billion U.S. market since 2008, according to Euromonitor. In some cases, the new options have better nutritionals. A cup of Silk almond milk has 50 fewer calories and two less grams of fat than the brand’s original soy milk.
Nut milk also doesn’t have the same association with genetically modified organisms (GMO) as soy milk, which Balsamo notes alienated some consumers. More than 90% of the soy harvested in the U.S. is genetically modified, which a rising number of consumers—especially the kind that might opt for soy milk—have been trying to avoid.