When Dr. Andrew Weil first brought his idea of a contemporary restaurant chain with truly healthy food to Sam Fox, the national restaurant mogul wasn't biting.

"Health food doesn't sell," Fox told the pioneer of integrative medicine and nutrition.

"It would if it was delicious," replied Weil.

But Fox, the chief executive officer of Fox Restaurant Concepts, a Phoenix-based company that’s opened 50 successful American restaurants in the past decade, remained skeptical.

“My first interpretation of what Andy had in mind was the hippie, granola, and seeds kind of place,” Fox recalled.

But then Weil invited Fox to his home to cook a meal for him. It only took a few bites for the wheels in Fox’s mind to start turning.

“I was blown away by the flavors,” Fox told Healthline. “The taste of the food was amazing.”

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A Restaurant is Born

The result of that fateful meal is True Food Kitchen.

It’s a restaurant that deftly merges Weil’s knowledge of healthy, good-tasting food and Fox’s restaurant business know-how.

The first restaurant, which opened in 2008 in the Biltmore Plaza in Phoenix, was an immediate hit.

But Fox and Weil continued to tweak the menu, which is largely inspired by the principles of Weil’s popular anti-inflammatory diet.

And the public is eating it up.

True Food Kitchen is now a booming, and many say groundbreaking, national restaurant chain.

In the past few years, the company has opened locations in Arizona, California, Colorado, Florida, Georgia, Illinois, New York, Tennessee, Texas, and Virginia.

More restaurants are scheduled to open later this year and next year in Chicago, Nashville, New York City, and Sunrise, Florida. In California, new eateries will pop up in Palo Alto, Pasadena, and Walnut Creek.

Each True Food Kitchen restaurant takes in between $7 and $10 million annually, with the San Diego site in Fashion Valley being among the most profitable, according to the San Diego location’s general manager, Anthony Viveros.

Those are healthy profits for any type of restaurant, let alone one that offers up healthy food.

“This is not a fad. People are waking up and really looking at the ingredients in the food they eat, and they are realizing that healthy food can actually taste great,” Viveros told Healthline. “I love that we can have some real influence on a large number of people about eating right and making good food choices. People who work here really believe we are making a positive difference.”

By the end of 2018, Fox said that True Food Kitchen, which has become perhaps his most successful chain, would have 30 restaurants nationwide.

“The success even surprised me,” he said.

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Not Your Mom and Dad’s Health-Food Restaurant

For decades, health-food restaurants have had a difficult time making a go of it.

It hasn’t helped that they’ve been lampooned relentlessly by comedians, sitcoms, and movies such as Woody Allen’s “Annie Hall” as places where pale, dreary people in sandals and tie-dye shirts unenthusiastically serve up bowls of alfalfa sprouts and mashed yeast.

Several well-intentioned entrepreneurs have tried and failed to overcome that image and capture the zeitgeist of American dining.

Remember the health food restaurant chain Good Earth?

Good Earth owner William Galt, board chairman at General Mills, had helped the legendary Col. Harland Sanders start the Kentucky Fried Chicken chain in the 1950s.

Galt attempted to make Good Earth work as a national chain in the 1970s.

For a while it looked like he’d succeeded.

Galt opened locations in 11 states, and Nation’s Restaurant News called the restaurant "probably the most prominent chain example of a health food concept.”

In 1980 General Foods purchased Good Earth. There was eventually a loss of interest and the corporation got out of the health food sector. Many of the locations were turned into Red Lobsters and Olive Gardens.

Ever since, health food eateries have been a tough sell. But that’s changing quickly.

In this internet age, diners know so much more about the food they eat, where it comes from, and the importance of nutrition.

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What’s On the Menu?

Restaurant industry observers tell Healthline that the restaurant-going public’s demand for healthy food that tastes good has reached a tipping point and has pushed the industry into new, uncharted waters.

Healthy restaurants are hot.

The industry finally caught up with Weil, who’s been touting the benefits of healthy food that tastes great for decades.

Weil’s philosophy is that food is medicine.

But, he insists, it doesn’t have to taste like medicine.

True Food Kitchen offers a wide selection of delicious vegan, vegetarian, and gluten-free options, along with meat and fish dishes. They also serve juices made to order.

True Food Kitchen tries to offer something for everyone.

Weil’s partnership with Fox has evidently unearthed the recipe for health food restaurant success: an unpretentious but upscale sit-down place with a knowledgeable, positive staff.

True Food Kitchen’s atmosphere has lots of open air, natural lighting, and earth tones.

The kitchen is in full view, and the menu is healthy but not strictly vegan. It serves responsibly sourced proteins like grass-fed beef, sustainably raised fish, and select produce.

True Food Kitchen is much more than kale and quinoa. However, those foods are on the menu. And the drinks are much more than sea buckthorn and acai, but they’re on the menu, too.

Dinner entrees include everything from sustainable sea bass to gluten-free, house-made turkey lasagna with spinach, ricotta, and organic tomatoes.

The salads include organic Tuscan kale, Mediterranean quinoa with cucumbers, olives, Peppadew peppers, cherry tomatoes, pole beans, feta, almonds, and oregano vinaigrette.

“The food’s ingredients such as chia and Anasazi beans offer vitamin- and antioxidant-rich properties and benefits,” according to the nonprofit United States Healthful Food Council (USHFC), which recently announced that True Food Kitchen has become REAL Certified, a nationally recognized symbol of culinary nutrition and environmental excellence.

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Healthy Restaurants Now in Fashion

True Food Kitchen is just the tip of a growing iceberg of health-conscious American restaurants that are now making healthy profits. And they’re sprouting up everywhere.

Tender Greens, a healthy, in-and-out-quick dining experience with more than 20 locations in Southern California, gets most of its fresh food from local farmers, ranchers, and coffee roasters.

Lyfe Kitchen, the “fast-fine dining” chain, is another healthy option with locations in California, Colorado, Illinois, Nevada, Tennessee, and Texas. In its press materials Lyfe Kitchen notes that the restaurant is“committed to the idea that great-tasting food can also be healthy, affordable, and convenient,” with dietary choices that appeal to flexitarians, vegetarians, omnivores, and vegans.

Others in this booming sector include Seasons 52, Urban Plate, Sweet Greens, and Café Gratitude.

And then there’s Evolution Fast Food, a San Diego eatery that bills itself as “the only vegan, fast-food, drive-thru restaurant in the world.”

But owner Mitch Wallis says it won’t be for long.

“We’ve been here 10 years, but only in the last couple years has it really taken off,” said Wallis, who’s been vegan since college and has dedicated his life to being an agent of change for ecological paradigm.

“There is an approaching critical mass of people that are realizing the power of their plate and the ramifications of changing your diet,” Wallis said. “As this wave is happening, it is raising the sea level and helping to create a buoyancy for our business, after years of struggling.”

Wallis opened a second vegan fast-food restaurant called Plants Power in nearby Ocean Beach in San Diego County a few months ago.

Last week they installed a drive-thru there, he said, to make it the second vegan, fast-food drive-thru restaurant in the world. He is opening a third in Encinitas, about an hour north.

“Our business has been booming and has given us the resources and presence in the market to expand,” said Wallis, who believes his restaurant is the future of fast food because it is based on science, rational principles, and public demand.

“How can it not be the future of fast food?” he asked. “I love places like True Food Kitchen, but I see those kinds of restaurants as the cherry on the cake. But the cake itself is fast food. The number one vehicle to create a real paradigm shift in America is a massive, 10,000-unit drive-thru fast-food vegan chain. I feel like that will have the biggest effect.”

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Fast-Food Getting the Message

While the new generation of eateries is embracing healthy dishes, many existing fast-food chains are also heeding the call.

Subway, the industry leader, has emphasized healthy eating for quite some time.

And now even the burger joints are changing their tune.

White Castle’s veggie sliders, for example, are popular, and the chain recently made all its buns entirely vegan. The company said in a recent statement, “We are committed to listening to our customers and keeping up with changing tastes by developing new menu items.”

Burger King’s veggie burger, the BK Veggie, has also been successful, although it still does include dairy products. Burger King also recently introduced a new way to make fries that reduces fat and calories.

Wendy’s recently began serving a vegan burger called the Black Bean Burger in a few cities such as Columbus, Ohio, and Salt Lake City, according to The Vegan Banana.

And the granddaddy of all fast-food chains, McDonald’s, has become much more health-conscious in the past few years.

As the New York Times reported in late 2013, the place with the golden arches and Ronald McDonald is no longer marketing some of its less nutritional options to children. It’s also including fruits and vegetables in many of its adult menu combinations.

McDonald’s has also added smoothies, premium wraps with grilled, instead of fried chicken, salads, egg-white McMuffins, and calorie counts.

As the Times reported, the healthier offerings at McDonald’s, which were announced in conjunction with the Clinton Foundation’s campaigns to reduce childhood obesity, are part of McDonald’s efforts to appeal to health-conscious customers with food choices that are lower in fat, salt, and sugar than its classic hamburger and french fries options.

But one McDonald’s executive evidently saw the writing on the wall and jumped ship. Don Thompson, the company’s former chief executive officer, reportedly left the company a few months ago and joined the board of advisors at Beyond Meat, a startup that is trying to move the public away from meat and toward plant-based foods with its “mock meat” burgers made of vegetables.

Ethan Brown, Beyond Meat’s chief executive officer, told New York Magazine last year that his dream is to have Beyond Meat’s veggie-based beef substitute in McDonald's “within five years.”

Other so-called fast-casual restaurants such as Chipotle, Corner Bakery, and Panera, are particularly popular with the millennial generation. Since the outset, these restaurants have been more health-conscious than the traditional fast-food places.

Restaurant industry observers tell Healthline that millennials simply do not have as much generational loyalty to the older fast-food chains.

Weil said all these steps are positive ones. “Existing chains are providing more information about their food now and more products for people with issues like gluten sensitivity or dairy and meat concerns,” he told Healthline. “It’s always a good thing for people to have more options.”

Even vegan food purists like Wallis agree.

“All of this is just another sign that we are moving toward healthier food, and a healthier planet,” he said.

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Yes is the Answer

Meanwhile, back at True Food Kitchen in San Diego, it’s a full house and things are moving fast.

Tihitina Berhanu, who’s worked as a server at this location since it opened four years ago, has several tables but takes a minute to stop and have a chat.

Berhanu said restaurants that serve healthy food should “by definition” convey a happy, healthy, positive vibe, and always accommodate the customer.

“Our motto is ‘Yes is the answer, what is the question?’ Everyone’s priority here is to make sure each guest leaves happy,” Berhanu told Healthline.

Berhanu said the servers have to meet a high standard.

“You need to know everything about the menu: every single ingredient, including in the sauces and dressings, nutritional benefits, drinks, all potential allergies in every dish and dressings, and ways to modify dishes to satisfy every guest’s specific dietary requirements,” she said. “Servers and bartenders get tested on the menu every season with the menu change.”