FDA Commissioner Dr. Scott Gottlieb told CNBC on Friday the federal agency is concerned that consumers are being "misled" about the nutritional value of nondairy products that use the term "milk."
"Are consumers who are using plant-based milk products by seeing the word 'milk' imputing a certain nutritional value into that beverage that they're not deriving?" Gottlieb asked on "Squawk Box."
Gottlieb argued the current definition of milk is something that comes from an animal that lactates. "Obviously, that doesn't fit the definition of a plant-based beverage right now."
The FDA could soon issue new guidance on what can be described as milk.
Gottlieb spoke about the plans in July, noting there are hundreds of federal "standards of identity" spelling out how foods with various names need to be manufactured. "An almond doesn't lactate, I will confess," Gottlieb said at a Politico summit in July.
However, he did concede on Friday, "If you look up the definition of what is milk in the dictionary, the second definition is a substance derived from a nut."
"There's a commercial speech issue here as to whether or not they can call themselves milk," he added.
The National Milk Producers Federation welcomed Gottlieb's concerns.
The group in July urged the FDA to review use of the term, saying "definitions are critical to safeguarding consumers from making purchases of products whose labels are false and misleading."
According to government filings, the dairy industry spent more than $2 million on lobbying efforts this year.
According to market research group Mintel, nondairy milk sales, including almond and soy milk, increased more than 60 percent between 2012 and 2017, while skim and low-fat dairy milk sales dropped over the same period.
Meanwhile, the Plant Based Foods Association has told the FDA "there's room for everyone" in the dairy category, adding "American consumers are sophisticated and well informed."
— AP contributed to this report.