(Washington Post illustration; iStock)

Researchers have known for decades that women tend to beat men on environmental metrics. They generally use less fuel and energy. They eat less meat. They're more concerned about climate change.

James Wilkie, a business professor at the University of Notre Dame, wanted to understand what drives this gender eco-friendliness gap. After years of exploring psychological bias, he and his colleagues developed a theory.

"Men’s resistance may stem in part from a prevalent association between the concepts of greenness and femininity and a corresponding stereotype (held by both men and women) that green consumers are feminine," they assert this month in the Journal of Consumer Research. "As a result of this stereotype, men may be motivated to avoid or even oppose green behaviors in order to safeguard their gender identity."

The researchers conducted a set of experiments, each designed to gauge if we actually do ascribe gender to green products and whether such perceptions impact our willingness to use them. They found people consistently connect environmentally conscious goods to their idea of femininity.

The first survey of 127 college students asked respondents if they thought green products appeared masculine, feminine or neither. Most participants, both men and women, said items designed to protect the planet seemed feminine.

Another group of 194 students took an online quiz instructing them to imagine two grocery store shoppers, one carrying a green reusable bag and another toting a plastic sack. The quiz asked: Which seemed more eco-friendly, wasteful, masculine and/or feminine? The green shoppers seemed to respondents more eco-friendly and feminine, regardless of their gender. The plastic shoppers came off as more wasteful and masculine.

The researchers next gave a group of men phony gift cards and told them to pick from a selection of batteries, which included a green option. In both a faux Walmart and an online shopping scenario, the men avoided the green choice. “Self-perceptions of femininity suggest that threats may also influence private behavior,” the authors wrote.

Wilkie’s team also found men in the studies were more likely to donate to an environmental nonprofit group that had a “masculine” logo — one with darker colors and bold fonts — than to an organization that displayed lighter tones and “frilly” letters. Logos didn’t have an impact on where women said they’d want to donate.

A similar trend emerged in an experiment at a BMW dealership. When presented with two versions of the same “green” car, men favored the one called the “Protection Model” over the “Eco-friendly Model.” Women, meanwhile, weren’t particularly swayed by either title.

“Stereotypical feminine behavior and attitudes are more in parallel with taking care of the environment,” Wilkie said of the findings. “Male traits tend to conflict with this idea of maintaining a nice environment for other people.”

Wilkie blames stereotypes. People who care about the environment are perceived as nurturing, gentle caretakers. Pop culture says they're barefoot hippies with long hair and flower crowns. That image clashes with traditional masculinity.

Previous research, Wilkie noted, suggests that men are socially penalized more for breaking gender norms when it comes to the products they use — or even the drinks they order. “If a man at a bar were to order a girlie drink, he might get some looks,” Wilkie said. “He might get some snickers. He might even get into a fight.”

A woman requesting something that reads masculine, such as, say, a whiskey on the rocks, probably wouldn’t encounter that problem. “Some people might even be impressed,” he said.

Carrie Preston, director of the Women’s, Gender and Sexuality Program at Boston University, said it’s concerning that feminine-seeming goods or actions repel some men. “That says what’s feminine is bad, is lesser, is second class,” she said. “Although men’s and women’s roles have changed significantly, masculinity hasn’t changed as much.”

Caring about what people think of your drink choice or grocery bag may seem silly. There’s nothing inherently feminine about recycling, and some would argue that femininity itself (and how it’s marketed) is a cultural creation. Still, a 2011 survey from the global marketing firm Ogilvy and Mather found 82 percent of adults in a nationally representative sample said “going green” is more ladylike than manly.

Marketers are unlikely to shatter gender expectations overnight — or nix the belief that feminine is lesser — but a packaging or messaging tweak could draw more men to the green movement.

"Despite a prevalent stereotype that green consumers are more feminine than non-green consumers," the researchers wrote, "we show that men’s inhibitions about engaging in green behavior can be mitigated through masculine affirmation and masculine branding."

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