CNN chief medical correspondent Dr. Sanjay Gupta spent a year traveling around the world to shed light on the debate about marijuana. Catch his groundbreaking documentary "WEED" at 8 p.m. ET Sunday on CNN.

(CNN) -- It was the pot story read around the world.

Dr. Sanjay Gupta is used to making headlines. The brain surgeon and CNN's chief medical correspondent can't even leave his office and walk through CNN Center without tour groups stopping him to take his picture or compliment his work. But this time the intensity of interest in a story he wrote for CNN.com about how he changed his mind about the effectiveness of medical marijuana was something even he didn't anticipate.

"The attention has been pretty intense, and I was a little surprised," Gupta said. "I know it's a provocative topic, but the science is there to back it up."

More than 330,000 people shared the story on Facebook, and it started to trend on Twitter. His column inspired pot jokes as well as thoughtful conversations in publications around the world.

Vanity Fair referred to him as the "Dr. Phil of actual licensed physicians." The Los Angeles Times said it wouldn't go so far as to call him Dr. "Feelgood" but remarked about his change of heart. The Washington gossip site Wonkette posted a story with the headline, "When you've lost Sanjay Gupta you've lost America: Sanjay Gupta wants to get 'high' on the pot like a common jazz criminal." Even the usually sober Washington Post used its piece as a jumping-off point to ask, "Is pot the new gay marriage?" Some polls show more than half of all Americans now support both same-sex marriage and marijuana.

While the majority of Americans may share his opinion, Gupta said the medical community has been a little slower to embrace it.

"I understand there is concern that if you legalize it, kids will use it recreationally, and I don't want young people to do that, but our concern for their safety shouldn't keep patients who need this from getting access," Gupta said.

After his article appeared Thursday, Gupta said he received calls and e-mails from people from all walks of life who were grateful he started the conversation.

Doctors, judges, politicians and clergy got in touch to thank him for speaking up. And of course, he's had to put up with a lot of pot jokes. But he called it an important message more people need to hear.

"I guess I've tapped into something that hit at the right time," Gupta said. "That, or it was a really slow news day."

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