UPDATE 2-Health websites merger to challenge WebMD

(Adds comments from Waterfront CEO)

By Esha Dey

BANGALORE, Oct 3 (Reuters) - Privately held online health sites Revolution Health Network and Waterfront Media agreed to merge in a deal that could challenge WebMD Health Corp's (WBMD.O) dominance in the health care space.

"We are not disclosing specific terms of the deal but the combined company will be valued at about $300 million," Waterfront CEO Benjamin Wolin told Reuters.

The combined company is projected to have more than 20 million unique users, the companies said, citing a comScore Media Metrix report.

The New York Times said the combined entity would have enough traffic in the United States to compete with WebMD, now the market leader in the online health category.

"We will be the market leader from a reach perspective with over 22 million units in the United States," Wolin said.

Waterfront currently has a user base of around 14.5 million and Revolution has about 12 million, with overlaps of about 17 percent, Wolin said.

The combined company will keep the name Waterfront Media and remain headquartered in Brooklyn, New York. Waterfront Media CEO and co-founder Wolin will remain the CEO of the new company.

"We think we have the wind at our back and can pass them," Steve Case, Revolution's founder, told the New York Times referring to WebMD. Case is also the co-founder of AOL, a Time Warner Inc (TWX.N) unit.

Credit Suisse acted as the financial adviser to Waterfront Media while Morgan Stanley advised Revolution Health Network on the deal.

Waterfront Media operates the Everyday Health Network, including its flagship site EverydayHealth.com. Revolution Health, under the Revolution LLC umbrella, runs the RevolutionHealth.com site.

WebMD could not be immediately reached for comments. (Reporting by Savio D'Souza and Esha Dey in Bangalore; Editing by Erica Billingham and Deepak Kannan)