SUNSET PARK — Fast food isn’t always considered the healthiest option, but diners can now alleviate at least some of that guilt by eating green.

Santa Monica-based Greenopia recently released a new rating system for the nation’s 23 most popular fast food restaurants, evaluating the eateries based on characteristics that include building design and corporate commitment to the environment.

Greenopia runs an online directory of eco-friendly products and businesses and publishes a local Zagat-style guide that includes everything from environmental friendly grocers to pet stores.

“There’s a really strong growth of interest in making sure that we’re both consuming non toxic and healthy foods but also doing that from organizations that are also conscious about the impact of doing business on the environment,” said Gary Bishop, the chief operating officer for Greenopia.

A team of researchers selected 23 of the most popular chains and rated them on a scale of zero to four leafs, evaluating the companies based on factors that include the carbon footprints of products served.

“If a company has a biodiesel fuel fleet of delivery vehicles, that is going to have a different impact from someone using rail or other modes of mass transit,” Bishop said.

He said that Greenopia plans to review the fast food eateries again in four to six months, noting that it takes time for restaurants to institute changes.

Among the recognized businesses that received less than four stars are Panera Bread and Peet’s Coffee.

Peets, which has locations on Montana Avenue and Main Street, operates a coffee roasting plant that has been certified as LEED silver by the U.S. Green Building Council, The coffee shop, which received two leaves, also provides a discount to customers who bring in their own mug, which cuts down on waste.

“This means that the roasting plant is extremely efficient and has a minimized impact on the environment,” the review stated.

Panera, which has a restaurant on Wilshire Boulevard, was recognized for incorporating responsible purchasing into its business practices. The restaurant also has organic and natural choices available on its menu and uses washable flatware for diners who eat in. The business still needs to tackle green building design issues, Greenopia said.

Pizza Fusion and Le Pain Quotidien were the only two companies that received a full four-leaf rating. Most of the chains did not receive even one leaf, meaning they are not considered green at all.

With the motto, “Saving the Earth: One pizza at a time,” Pizza Fusion specializes in organic pies, sandwiches and salads. The company currently has 20 locations in the United States, a number that is slated to increase to 75, including one on Ocean Park Boulevard at 29th Street.

According to Greenopia’s review of the business, Pizza Fusion delivers using hybrid vehicles. All Pizza Fusion projects are also LEED certified.

The only issue with the business is it lacks a comprehensive sustainability report, the review stated.

David Whitworth, who owns the Santa Monica franchise, said his restaurant will follow in line, buying locally grown organic ingredients, delivering with its hybrid vehicles and having its employees wear 100 percent organic cotton uniforms.

The restaurant, which is being built using green materials, is expected to open in May.

“It’s work but it’s enjoyable work,” Whitworth said. “(The green practices) will hopefully bleed off into other businesses that say ‘I may want to do this too.’”

melodyh@smdp.com