CNN Weed Dr. Sanjay Gupta Reports July 13, 2014 23:34:00
Biggest reasons most people think pot is safe. in fact, a new study of children showed that by high school only one in five think marijuana is harmful. that's the lowest number in more than two decades, and it's something we heard over and over as we travelled around the country. >> not really that harmful. >> it has a lot of benefits. not really too concerned about it. >> i think it's safe if you're a safe person. >> but the experts we spoke to said there is more to the story. >> there are people who compulsively smoke, who want to stop smoking, but they can't stop smoking. >> in fact, 9% of ...