Low-cost reality lifestyle programming aimed at female audiences – from Hoboken cake bakers to pro house flippers — has acted as a kind of revenue growth hormone for cable TV programmers over the last decade.

And as they look to take a huge bite out of traditional TV’s nearly $50 billion in annual advertising spending over the next two years, big digital video companies Yahoo and YouTube are taking particular aim at the women’s lifestyle programming segment.

Trumpeting the debuts Monday of three new female targeted shows on Yahoo starring So You Think You Can Dance host Cat Deeley, designer Rebecca Minkoff and comedian and Chelsea Lately regular Michael Yo, as well as the renewal of five other programs from the portal’s women’s slate, Erin McPherson, who heads the acquisition and development of video programming for Yahoo, called the female 25-54 audience a “core demo” for her company. “It’s not just key for us, it’s key for our advertisers,” she said. “It’s a great place to start.”

On cable, channels like NBCUniversal-owned Bravo have blossomed in recent years, growing revenue from $42 million in 1996 to $530 million in 2010, while offering packaged goods sponsors an efficient way to reach female audience segments.

With Yahoo offering channel sponsorships and various brand-integration opportunities to advertisers like Procter & Gamble, McPherson believes there’s no reason why Yahoo can’t take a bigger chunk of that advertising market away from cable.

“That is definitely part of the message we want to communicate to advertisers,” she said. “We are reaching an audience that in numbers rivals cable. And it’s a deeply engaged audience.”

According to a report in Adweek Monday, YouTube is already selling sponsorships for its “mom”-targeted channels to big-name automotive brands such as Toyota for as much as $6 million a year.

Meanwhile, for programmers targeting the female lifestyle segment, partnering with video portals like YouTube provides a lower cost barrier to entry than the now largely unionized world of basic cable production.

On Monday, for example, Meridith Corp. announced the launch on YouTube of DIGS, a home- and garden-themed lifestyle channel similar to cable’s DIY Channel.

Housing lifestyle-themed print brands such as Better Homes and Gardens, Parents, Ladies Home Journal and Family Circle, Meredith now has a platform that will let it extend its portfolio into video, targeting what Meredith chief video officer J.R. McCabe calls the “chief household officer” without incurring the risk of starting a cable network.

This downside, of course, has been laid bare by recent cable start-up the Oprah Winfrey Network, which could lose backers Discovery Networks and Harpo Productions as much as $143 million this year, according to an SNL Kagan projection.

Not only does YouTube shoulder some of Meredith’s production costs, it also helps the company reach sponsors.

“There are ways to make investments in today’s media, and we want to do that in a way that’s smart for us,” McCabe said.

Image via Shutterstock by Inga Ivanova.