Vegetarian food advocates take note: You could be spreading more of the good vegetable word by working smarter, not harder.

This is the message Nick Cooney, author of the new book “How to Be Great at Doing Good,” will bring to this year’s Vegetarian Food Festival, sponsored by the Maine Animal Coalition. Now in its 11th year, the annual celebration of Maine’s plant-based culture takes place from 11 a.m. to 3 p.m. Saturday at the East End Community School in Portland. Admission is free.

“All of us – whether we consider ourselves activists or occasional volunteers or donors – we all should realize we could be making smarter charity decisions that would do more good for the world,” Cooney said by phone from his office in Washington, D.C., where he serves as director of education for Mercy for Animals.

Known for recording undercover films inside animal barns, Mercy for Animals conducted an investigation at the former Decoster Farm, a trouble-plagued egg farm in Turner in 2009. The investigation led to Quality Egg of New England being fined more than $130,000.

Cooney is also the author of “Veganomics” and “Change of Heart,” and his stop in Portland is part of a cross-country tour for his latest book.

Cooney uses the psychology around social change and effective messaging to craft his advice. He said what can trip up advocates of vegetarianism is when they let their outrage over conditions on factory farms guide their actions.

“The approach that will create the most change isn’t us clearly and loudly expressing what we want people to change,” Cooney said. “If we want to change other people’s behavior, we have to think backwards (from the change we want to happen), and we’ll often come to a very different approach.”

For instance, when a meat lover challenges a vegetarian at the dinner table about his or her diet, the vegetarian’s best response is not to shout “Meat is murder!” Instead, Cooney advocates a “short and sweet answer that makes intuitive sense.”

Cooney doesn’t cite scientific studies or detail what was found in undercover investigations when he’s asked about his diet. Instead he’s likely to say something like: “Once I realized that I could be happy and healthy without causing all the suffering that goes on at these farms, I stopped eating meat and am glad I did.”

Michael Angelone, who serves on the Maine Animal Coalition board and is coordinating this year’s festival, said the organizers invited Cooney because of his unique perspective and expertise.

“People can get a lot of information from him if they’re interested in being an activist,” Angelone said. “I think he’ll be inspirational and give practical ideas on how to persuade people.”

Cooney’s talk takes place at 12:45 p.m.

Festival attendees interested in health can catch a return appearance by Falmouth-based orthopedic surgeon and plant-based diet advocate Dr. John Herzog. He’ll speak about “Health Care Is Caring for Your Health” at 11:15 a.m.

“The talk will be focused on what you can do to take care of your own health,” Herzog said. “I will get into the latest science on diet and microbiome as the key in atherosclerosis – 70 percent of our 12-year-olds have it.”

In addition to atherosclerosis – also known as heart disease – and digestive bacteria, Herzog will talk about diet’s relationship with obesity, diabetes and cancer.

The festival, which typically attracts close to 800 people, takes place in an LEED-certified green elementary school at the top of Munjoy Hill.

The school features an array of solar panels, a living roof and a natural playground, with a new garden for teaching about bugs, birds and butterflies. The school has a wide lawn with commanding views of the community gardens and orchard across the street and Back Cove and the city spread out below.

In the sunny cafeteria, festival attendees can buy lunch and enjoy it at the tables inside or outside on the lawn.

The popular raw food vendor Here Comes the Sun Vegan Bus from Raymond, New Hampshire is returning to the event this year with smoothies and raw treats. The bus is really just Christina Cretella and her daughters, Xavia, 17, and Elena, 13.

The mother and daughters sell food at vegetarian and healthy living events and donate most of their proceeds to animal rights causes. The team is using the stop at the Vegetarian Food Festival in Portland to kick off a 2015 summer tour of all 50 states.

“Last year, there were wonderful people and a great community feeling,” Christina Cretella said. “There was good food and good organizations to support.”

The bus crew’s Beatles-themed menu includes an Eleanor Rigby (green tea chai), Twist and Shout (banana and chocolate) and the most popular Here Comes the Sun (orange juice, strawberries, goji berries and coconut water). You’ll also find kale chips, raw cheesecakes and raw chocolate.

The Portland Food Co-op will be selling a full lunch, with an all-vegan, almost-all-organic menu of gazpacho, triple bean salad, hummus veggie wraps, dessert bars and drinks. And the Oakhurst Dairy plans to donate 36 half-gallons of its new almond milk to the event and it will be served in sample cups and over granola.

Members of the Maine Vegan Meetup plan to gather at noon in the cafeteria for lunch and a half-hour of socializing between scheduled events.

Information tables will fill the gymnasium, and among this year’s exhibitors are Frinklepod Farm, the Maine chapter of Physicians for Social Responsibility, The Good Life Center founded by the late Scott and Helen Nearing, Sea Shepherd Conservation Society, Garbage to Garden composting, Environment Maine, Vegan Outreach, Peace Ridge Sanctuary and 46 Million Turkeys.

A 2 p.m. screening of the 2014 environmental documentary “Cowspiracy” closes out the festival. The film contends that mainstream environmental groups often ignore the pollution caused by the meat industry.

In recent years, a handful of festival-goers have arrived in costume. This year, Angelone said, “we’re asking people to dress up as their favorite vegetable or farm animal.”

Anyone who comes dressed as a carrot or a cow will go home with a free tote bag filled with vegan goodies. And if these costumed activists listen to Cooney, they’ll also leave with a smarter way to advocate the pro-vegetable agenda.

Avery Yale Kamila is a freelance food writer who lives in Portland. She can be reached at:

[email protected]

Twitter: AveryYaleKamila

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