Sales of plant-based foods grew 10 times faster than their animal-based counterparts last year, reflecting the growing popularity and prevalence of alternative protein sources in U.S. grocery stores and restaurants.

The data, compiled by Nielsen and published by the Plant Based Foods Association (PBFA), looks specifically at plant-based foods that directly replace animal products such as seafood, meat, eggs and dairy. The report shows rapid expansion within these grocery-store segments at a time when federal regulators are revisiting how to categorize these foods based on consumer expectations.

Plant-based food sales leapt 20 percent last year while overall food sales in these same categories grew just 2 percent.

The animal-based protein category is far more mature and much larger, giving it less room for growth. For instance, the entire meat market is around $85 billion, with plant-based substitutes accounting for $670 million in sales.

Still, improvements in taste, variety and competition have all led to the mainstreaming of plant-based foods, said Michele Simon, executive director of PBFA. Consumers are mixing and matching meat and meatless options into their diets.

“The plant-based foods industry has gone from being a relatively niche market to fully mainstream,” Simon said in a statement. “Plant-based meat and dairy alternatives are not just for vegetarians or vegans anymore.”

Packaged-food companies that have struggled to grow sales of its traditional products are investing in fast-growing plant-based products. 301 Inc., the venture arm of Golden Valley-based General Mills, has invested in three companies in the plant-based protein space: No Cow, Kite Hill and Beyond Meat. Cargill Inc., one of the world’s largest sellers of beef, formed a joint venture with Minneapolis-based Puris, which makes pea protein. And Austin, Minn.-based Hormel Foods Corp. now offers a plant-based protein-shake product under the Evolve brand.

At $1.6 billion, milk alternatives, such as soy or almond, account for about half of all plant-based sales, which topped $3.3 billion last year.

With a seemingly endless stream of new sources — such as oats, hemp or peas — plant-based milks grew another 9 percent last year and now constitute 15 percent of all milk sales. By contrast, traditional cow’s milk sales were down 6 percent last year, spurring the dairy industry to seek intervention from U.S. Food and Drug Administration.

Two weeks ago, FDA Commissioner Scott Gottlieb announced his agency would spend the next year gathering and reviewing input and research on dairy alternatives.

“We want to see if inherent nutritional characteristics and other differences between these products are well-understood by consumers when making dietary choices for themselves and their families,” Gottlieb said in prepared remarks.

Gottlieb commended the food industry for its innovation in developing new products that respond to consumers’ quest for healthier options, he tempered that by questioning if consumers are getting the protein levels and added vitamins they assume.

Addressing these and other efforts to regulate plant-based product terms, Simon of PBFA said, “It is important that regulators and legislators treat our industry fairly and the playing field for plant-based foods is level and fair at the state and national levels.”