Vegetarian and vegan cookbook author Nava Atlas remembers when she and her husband would be the lone non-meat eaters at Thanksgiving.

They’d politely pick around side dishes and sidestep questions about their choice not to eat meat.

Not anymore.

Plant-based diets are enjoying more acceptance these days, even on Thanksgiving, widely known as Turkey Day.

“It used to be a vegetarian or vegan was viewed as a sort of weirdo, but now when you say you’re following a plant-based diet, people look at you with admiration,” said Atlas, who lives near the Hudson River Valley in New York and has followed a vegetarian diet for 40 years. Thirteen years ago, she transitioned to vegan, which means not eating animal byproducts or using animal products as well.

To be sure, turkey is still king for Thanksgiving, with an estimated 46 million of the waddling fowl eaten for the 2013 holiday, according to the National Turkey Federation.

But there are growing numbers of people who are simply eating less meat, subscribing to calendar events such as “Meatless Mondays.”

Thirty-six percent of people report they are choosing a vegetarian meal at least twice a week, according to a 2015 Harris Poll commissioned by the Vegetarian Resource Group.

The number of vegetarians — who do not eat meat, fish or fowl — represents about 3.4 percent of the U.S. population, the poll reported.

As vegetarian meals become mainstream, the motivation for choosing a plant-based diet has shifted.

While the treatment of animals used for food remains an important motivator, it has become eclipsed by health concerns, said Eric J. Pierce, who does market analysis for New Hope Natural Media’s NEXT Data & Insights.

“What drives someone to choose a vegan or vegetarian diet has become more diversified,” he said.

Meanwhile, the latest proposed changes to the U.S. dietary guidelines suggest Americans should eat more fruits and vegetables, while restricting intake of red and processed meats.

The market for vegan or vegetarian food exceeded $2.46 billion in 2014 and is expected to more than double by 2020, according to data collected by New Hope’s Nutrition Business Journal.

During Thanksgiving, the best-known vegetarian alternative is the Tofurky, which became the butt of many jokes on late-night television when it was launched in 1995. The Tofurky Co., based in Hood River, Oregon, sold 500 of its “roasts” that year, and continues to garner attention each holiday.

“It struck a chord in the imagination of people and got us a great deal of publicity that we really couldn’t have afforded at the time,” said Seth Tibbott, founder and chairman.

The company also got a lot of feedback from consumers, who praised the product for allowing them to stop feeling like “second-class citizens” at Thanksgiving, Tibbott said.

As sales of Tofurky grew, so did its consumer market. While the original roast was designed to feed a large vegetarian gathering, the company soon discovered its true market was for meat-centered meals whose guest list included some vegetarians.

The company rescaled its roast to be served alongside a Thanksgiving fowl and now non-vegetarians purchase the most Tofurkys.

More than 3.8 million have been sold since 1995 and the company is on track to sell more than 320,000 of the 26-ounce roasts this year, mostly from mainstream grocery stores.

“We’re not just in co-ops or natural food stores anymore,” Tibbott said.

And Tofurky isn’t the company’s biggest seller. Once representing more than half its sales, the roasts now comprise about 15 percent. Vegetarian versions of deli meats, and sausages now represent a greater part of the business. In addition, the company recently launched a roast chicken substitute.

“More people are open to (meat alternatives) now, mainly because they’ve gotten a lot better,” Tibbott said.

Greater awareness of food production and its impact on the environment has pushed plant-based diets into the forefront, Atlas said.

She said acceptance has increased due to several factors, including news coverage of high profile people shifting to plant-based diets, such as former President Bill Clinton; the globalization of U.S. dining palates; and wider access to produce and better-tasting meat alternatives,

Atlas, whose books include “Vegan Holiday Kitchen,” said Thanksgiving is well suited for those following plant-based diets because of the holiday’s link to celebrating the harvest.

“Thanksgiving wasn’t to commemorate a turkey or fowl, it was to celebrate squashes, corn, beans and all the different garden vegetables that those who had newly arrived to the Americas were learning to grow,” she said.

Atlas, who shifted to a vegan diet 13 years ago, suggests heart-healthy recipes such as winter squash stuffed with grains and nuts, hearty soups packed with legumes and vegetables and simple adjustments such as cooking a meat-free, apple-walnut stuffing apart from the bird to create a more inclusive Thanksgiving table.

“They’re heart-healthy and don’t leave person like they’re being deprived of anything,” she said.

Atlas avoids speeches about her diet at the Thanksgiving table, instead she brings a large vegan entrée and dessert to Thanksgiving parties to share as a way to get her message across.

“Everyone always ends up wanting what we’re eating and it’s a great way to introduce people who may be skeptical about how good it is,” she said.