Former NBC Universal executive Lauren Zalaznick has joined fashion and style website Refinery29 as a strategic adviser as the site aims to continue an expansion into a lifestyle site aimed at millennial women. The company is expected to announce Ms. Zalaznick's appointment on Wednesday.

In the part-time consulting role, Ms. Zalaznick, who was an architect of the Bravo Network, will help the site's founders develop strategies around producing a wider range of content and doing more of it with video. Refinery29 last year raised $20 million, part of which was earmarked to create more video.

"I'm going to help find ways to take the type of Refinery29 content that already connects with their audience to a more entertainment focus around style, fashion and pop culture," Ms. Zalaznick said.

The role, which is unpaid but gives Ms. Zalaznick an equity stake in Refinery29, is "meant to accelerate growth at a critical time for a very healthy company," she added.

During her 12-year run at NBC Universal, Ms. Zalaznick oversaw cable networks like Bravo, Oxygen and Style, as well as digital networks Fandango and Daily Candy. She left NBCU at the end of 2013 after control of the cable channels was given to Bonnie Hammer amid a restructuring at the company.

Since then, Ms. Zalaznick has taken on a variety of advisory roles, including as a board member at Shazam, maker of the audio-recognition app. She is also an angel investor and the editor of her own email newsletter, "LZ Sunday Paper," which is popular among media executives.

The appointment of Ms. Zalaznick comes as Refinery29, which debuted in 2005 as a local shopping guide, is pivoting from its narrow and deep focus on fashion to covering broader topics such as entertainment and wellness. So far stories about how to make almond milk at home -- one of its most popular this year -- are helping draw a larger audience, with unique visitors reaching nearly 8 million in May, a 327% spike from the previous year, according to ComScore.

Revenue has grown as well, according to Refinery29 co-founder and co-CEO Justin Stefano. This year, the site expects to roughly double last year's revenue of $29 million, he said.

It has also hired 40 people since Jan. 1, bringing total employees to 175.

Last year, the site was "around break-even" in terms of profitability, Mr. Stefano said. It's "a little above break-even" this year. In October 2013, the company picked up $20 million in Series C funding led by New York based private equity and venture capital firm Stripes Group. That brought the site's total funding to about $30 million, with earlier investments from Hearst, Lerer Ventures and others.

Expanding beyond the tight focus on fashion comes with its share of risks, namely that covering food, entertainment and wellness could water down the site's content and turn off readers who look to Refinery29 for fashion and style coverage, not recipes for strawberries or the latest "Gone Girl" trailer. There is also a glut of coverage in areas like food and entertainment online, where competition and automated ad tech are putting downward pressure on prices for display ads.

None of Refinery29's ad inventory is now sold through automated auctions, according to Mr. Stefano, who said he's "learning more about it."

And the site's founders say its new territory is natural for the brand. "Our whole thesis is that style is everything," said Philippe von Borries, co-founder and co-CEO of Refinery29. "Style really informs all parts of your life. That's become mission critical for us: capturing style that influences your home, your beauty, how you eat and workout."

"We've challenged the notion of fashion and shopping since the beginning," he added. "It goes beyond the closet, to music, beauty and even culture. It's about being at the heart of that conversation."

The approach is attracting advertisers outside of fashion and beauty to the site, including Cadillac, which was Refinery29's first big relationship with a car company, according to Mr. Stefano.

"We've been seeing growth in new categories, but we need to be careful and we need to do it the right way," he said. "Fashion and beauty are still our core. We need to be careful to not lose sight of that."

Nearly all of Refinery29's revenue stems from advertising on the site, with a heavy focus on native ads and branded content. About 60% of its advertising programs include content, such as a list of must-have fashion accessories from the site's editors. A brand might sponsor that list, which may not include an item from the brand, with a banner ad adjacent to the list.

"They've been a really great partner for brands in developing content that could live on and off Refinery29," said Shenan Reed, president-digital at MEC North America, a division of the GroupM media buying conglomerate. "They understood the need to move beyond the banner and into storytelling."

For Refinery29 to succeed in areas outside fashion, it needs to retain the voice for which it's become known, according to Ms. Reed. "If I like their point of view, then I want it in areas like lifestyle and wellness," she said. "They're like that girlfriend you trust because she's fabulous."

The site has managed to cultivate a loyal readership within the demographic of young women and explain this connection to the ad community. In June, the company filled an event space in Manhattan with media buyers and marketers to explain the results of a study it performed on millennial women.

"They're really aware of who their user is, what she's passionate about and how to talk to her the right way," said Brent Poer, president at digital agency LiquidThread, who attended the event.