A popular Web site that claims to tell users their biological "age" based on a series of health and lifestyle questions is also selling user information to drug companies, according to a report in the New York Times.

RealAge.com, which has achieved popularity through its affiliation with Oprah regular, Dr. Mehmet Oz, assigns users a "biological age" based on their answers to 150 questions. Lucky or "healthy" users usually find themselves assigned ages several years younger than their actual ages, whereas “unhealthy” users are told they’re biologically older than their chronological years.

But it's what RealAge.com does with that information from users that's raising eyebrows.

According to the Times, pharmaceutical companies pay RealAge.com to compile the test results of its members and send them marketing messages by e-mail. The drug companies can even target users at risk for conditions such as high cholesterol or hypertension with their own e-mails.

RealAge.com says the intent is not to violate users’ privacy but instead to target them with useful information. The Web site does warn users that it will "share" their information with third parties.

“Our primary product is an e-mail newsletter series focused on the undiagnosed at-risk patient, so we know the risk factors if someone is pre-hypertensive, or for osteoarthritis,” Andy Mikulak, the vice president for marketing at RealAge.com, told the Times. “At the end of the day, if you want to reach males over 60 that are high blood pressure sufferers in northwest Buffalo with under $50,000 household income that also have a high risk of diabetes, you could."

Click here to read more on this story from the New York Times.