A woman's place is in the boardroom — if you want a better-run business, that is. Corporate boards with greater gender diversity function better, and it takes just one woman to make a difference. While earlier research suggested that it takes a few women in the boardroom to move the needle, a new study shows that even the presence of a single female board member has a positive impact, especially in male-dominated industries.

"There's been this number out there that you need three women on the board to make a difference. What I find is you don't need three," said Judy Zaichkowsky, marketing professor at Simon Fraser University in Vancouver, Canada, and author of the new research. "The idea that you need to have this big critical mass is not shown out in the data," she said.



Rene Mansi | E+ | Getty Images

Zaichkowsky looked at corporate governance rankings of large, publicly traded Canadian companies over an eight-year period and found that while more female board members correlated with a higher ranking, companies started to see benefits as soon as they added their first woman to the board.

More from NBC News:

Your Racy Photos Are 'Fringe Benefits' at NSA: Snowden

Keystone Pipeline Foes Fear Worst for Water Supply

What Does America's 'Main Street' Look Like Today? The "critical mass" idea came from the theory that a single female board member would be perceived as a token with little ability to affect change, but women today who make it to the upper echelons of corporate power don't see themselves that way, said Shirley Davis, a consultant who works on global workforce and talent management strategies. "Being a strong female leader in that boardroom is going to give them license to speak up more," she said. "Women will talk out loud about how they feel about things."

Zaichkowsky found that the impact was greatest in male-dominated sectors like mining and energy. She speculated that women make boards function better because they focus more on details and push their fellow members to do the same. "I think people pay more attention when it's a diverse group," she said.

Read MoreBet on women with Barclays' new index