"TV personality Dr. Sanjay Gupta has reversed his opposition to medical marijuana — and admitted he's even tried the drug himself. "Well, I am here to apologize," Gupta wrote in an editorial posted on CNN's website. "I apologize because I didn't look hard enough, until now," he explains. "I didn't look far enough. I didn't review papers from smaller labs in other countries doing some remarkable research, and I was too dismissive of the loud chorus of legitimate patients whose symptoms improved on cannabis." In a 2009 op-ed for Time magazine entitled "Why I Would Vote No On Pot," Gupta wrote, "I'm constantly amazed that after all these years — and all the wars on drugs and all the public-service announcements — nearly 15 million Americans still use marijuana at least once a month. However, Gupta said he's now conducted enough personal research — including smoking cannabis himself. In an interview with CNN colleague Erin Burnett on Thursday, Gupta acknowledged he's smoked marijuana but admitted the side effects made him "paranoid." While Gupta still says he doesn't believe people should try pot until they are adults, he gave a list of reasons for why his opposition to marijuana has softened, citing what he describes as the drug's low potential for abuse and dependency, and legitimate medical applications. "In fact, sometimes marijuana is the only thing that works," Gupta wrote. He also cited a recent study showing that 76 percent of doctors say they approve of medical marijuana for treating pain in patients with cancer. "I promise to do my part to help, genuinely and honestly, fill the remaining void in our knowledge," Gupta wrote. Gupta is producing a new documentary on medical marijuana, entitled "Weed." It is scheduled to air at 8 p.m. ET on Aug. 11 on CNN."