FDA asks: Is almond milk or soy milk really even milk?

Combined ShapeCaption
A new study, published in the American Journal of Clinical Nutrition, found that each daily cup of non-cow's milk was associated with 0.15 inches lower height than average.

In a blow to plant-based milk enthusiasts, Food and Drug Administration Commissioner Scott Gottlieb on Tuesday announced a crackdown on "standards of identity" for non-dairy milks.

» RELATED: Cockroach milk may have more nutrients than regular milk, study says

"An almond doesn't lactate, I will confess," Gottlieb said in a keynote address at POLITICO's Pro Summit, citing the FDA's standards reference milk to a lactating animal.

“[These] are basically regulations that define recipes for how products need to be manufactured in order to call themselves, for example, ketchup. How many tomatoes do you need to actually call something ‘ketchup,’” he said.

» RELATED: This is the healthiest 'milk,' study says

Today, there are a variety of plant-based “milks” on the market, including soy, almond, coconut milks, not to mention multiple dairy alternatives.

Cow’s milk and soy milk contain about 8g of protein per cup, whereas almond, coconut and rice milk contain only 0-1g of protein per cup.

Here are some key differences in calories, protein and more among the five, composed by NBCNews.com:

  • Dairy milk: 110 calories; 2.5g fat (1.5g sat fat); 8g protein; 12g carbohydrate; 12g sugar; 0g fiber
  • Soy milk: 110 calories; 4.5g fat (0.5g sat fat); 8g protein; 9g carbohydrate; 6g sugar; 2g fiber
  • Almond milk: 30 calories; 0g fat (0g sat fat); 1g protein; 1g carbohydrate; 0g sugar; 1g fiber
  • Coconut milk: 45 calories; 4.5g fat (4g sat fat); 0g protein; 1g carbohydrate; <1g sugar; 0g fiber
  • Rice milk: 120 calories; 2.5g fat (0g sat fat); 1g protein; 23g carbohydrate; 10g sugar; 0g fiber

» RELATED: When to buy organic and when to save your money

The National Milk Producers Federation "welcomed Gottlieb's recognition today that the labeling practices of many plant-based dairy imitators violate long-standing federal standards," NMPF spokesman Chris Galen said in a statement, according to ABC News.

"The move would be a major boon for dairy groups, which have been struggling amid dropping prices and global oversupply," POLITICO reported. "The industry has petitioned FDA to enforce marketing standards for milk, but the agency has not previously addressed the issue."

Gottlieb said the plan to redefine the rules for milk products is going to take some time and lawsuits against the agency are expected, because “if you open our standard of identity, it talks about a lactating animal but if you open a dictionary, it talks about a milk coming from a lactating animal or a nut,” he said.

Read FDA's milk guidance documents and regulatory information.