Vegetarian is hot. Vegan is even hotter. But what about raw diets, the extreme and sometimes labor-intensive end of the healthy eating spectrum? That's much cooler. By design.

It also can be off-putting. For mere mortals unable or unwilling to hire personal chefs to manage the often time-consuming recipes involved in raw diets, it's a way of eating that can seem mostly out of reach. But chef Matthew Kenney - a pioneer of the movement that denounces meat, dairy and cooking produce above a certain temperature - believes the trick to making raw diets accessible is to make them less strident.

It's a movement that's been hindered by an all-or-nothing mentality, says Kenney. Proponents need to accept that most people won't be able to maintain a raw diet all the time.

"For raw to be successful and sustainable as someone's diet, we need to say, 'The more that we can eat of foods that are raw, that aren't processed, that are in their natural state, the better,'" Kenney said recently during an interview at the South Beach Wine and Food Festival. "Raw has just needed to be more inclusive and more flexible."

Which is to say, there's nothing wrong with eating an arugula salad that contains cooked squash, he says.

While vegan went seriously mainstream in recent years - thanks in part to potent celebrity endorsements from the likes of Beyonce, Jay Z and former President Bill Clinton - raw has struggled to win converts. It's at least partly due to a focus on laborious recipes - some of which take days to make - rather than the simple, delicious beauty of food in its natural state, Kenney said.

"This has been a second barrier for entry for many people. They think that raw cuisine is something that has to be out of a book," said Kenney, whose restaurants, M.A.K.E. in Santa Monica, California, and The Gothic New England in Belfast, Maine. "The simple, everyday cooking can be a sliced tomato and a sliced avocado."

Kenney will open his first fast-casual restaurant in Culver City, California, next month that will include raw foods such as salads and granolas, as well as cooked vegan quinoa bowls and toasts to appeal to a broader audience. He also runs the Matthew Kenney Academy culinary school, which specializes in raw cuisine.

He says making plant-based foods more appealing will require that chefs be taught how to treat vegetables, especially expensive ones like avocadoes, the same way they would an expensive piece of meat or fish.

It's also a matter of teaching them that simple can be wonderful. One of his favorite daily lunches takes only a few minutes to assemble with some shaved vegetables, greens, sauerkraut, nori and avocado. "It's recognized that something in its raw state is better and now it's just a matter of teaching people how to incorporate it into their day to day lifestyle without all the rules because it just sets people up for failure."