The meatless burger is becoming more popular, even among meat-eating consumers.

Some 95% of people who purchased a plant-based burger this year also ate meat, new data from market researcher NPD Group shows.

Some 228 million servings of plant-based burgers were purchased at quick-service restaurants this year, up 10% from a year ago. And while beef burgers are still the most popular burger on menus, with 6.4 billion ordered, growth is flat compared with a year ago, according to the report.

“ ‘U.S. consumers have not given up on beef burgers, but are willing to mix things up every now and them.’ ” — Darren Seifer, NPD

The substantial year-over-year growth in plant-based burgers is due primarily to greater availability at major fast-food chains including Burger King QSR, +1.17% and White Castle.

While vegetarians and vegans are contributing to the growth in the plant-based market, they still make up a small, single-digit percentage of the U.S. population and thus are not the main contributors to market growth, NPD food analysts note.

Some 18% of the adult population is trying to incorporate more plant-based foods into their diets, according to the report, and 60% of U.S. adults want more protein in their diets.

“Plant-based burgers allow consumers to substitute without sacrifice. They get the ‘burger’ experience while assuaging their need for more protein and social concerns,” says Darren Seifer, NPD food and beverage industry analyst. “U.S. consumers have not given up on beef burgers, but are willing to mix things up every now and then.”

The hype is hotter than ever as major fast-food chains jump on the bandwagon. Burger King announced earlier this year that it would take its Impossible Whopper — made from soy protein, potato protein, coconut oil, sunflower oil and heme, a molecule that makes the burger look and “bleed” like meat — national by year-end.

Last month, California-based Tex-Mex chain Del Taco sold 2 million of its meatless tacos made with plant-based substitute Beyond Meat two months after its launch, inspiring the chain to roll out meatless burritos.

The consumer trend toward meatless meals is making its way into at-home kitchens, too. Beyond Meat enthusiasm sent shares of meal-kit company Blue Apron APRN, +6.27% soaring when the latter announced it would add Beyond Meat plant-based proteins to its menus beginning in August.

Still, dietitians say that ordering a plant-based burger at a fast-food restaurant isn’t necessarily much healthier than eating a regular beef patty, especially if you order fries with it. When you factor in sodium, calories and fat content, plant-based burgers mimic the nutritional profile of their meaty counterparts.

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The demand for alternative protein is spawning food-cloning companies. Technology at Boston-based company Ginkgo Bioworks is being used in its food startup Motif Ingredients to replicate the texture and taste of foods like meatballs, chicken nuggets, cheese and yogurt with alternative proteins.

The laboratory technology develops ingredients that could be used in place of dairy, eggs and meat using amino acids, enzymes, vitamins and other ingredients through fermentation with genetically engineered years and bacteria for protein substitutes.

Part of the plant-based appeal is it entices consumers to cut out red-meat consumption. Studies have shown that red meat is “not essential” for diets, and has been linked to health risks, as well as environmental degradation.

Nutritionists advise cutting out excessive amounts of meat and replacing the protein source with plants like legumes, vegetables and nuts.

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Shares of Beyond Meat BYND, +4.81% are up nearly sevenfold from the company’s $25 IPO price, while the Dow Jones Industrial Average DJIA, +1.33% is up more than 11% in 2019, and the S&P 500 Index SPX, +1.59% is up just less than 15% since the start of the year.

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