Your first link does not provide any information regarding the safety and long-term effects of medical marijuana in the human body. It simply states there are 1.2 million medical marijuana patients in the United States. Just because 1.2 million people use a particular substance does not make it safe. Opiates and alcohol are both examples of substances that are quite safe in moderate amounts, but they can have adverse effects and potential for addiction if not used properly.

I don't have a .PDF reader set up on my laptop, so I cannot look at the data from the second link at the moment.

Your cherry picked information out of your third link to support your argument while ignoring the researchers statements. "Suicides among men aged 20 through 39 years fell after medical marijuana legalization compared with those in states that did not legalize. The negative relationship between legalization and suicides among young men is consistent with the hypothesis that marijuana can be used to cope with stressful life events. However, this relationship may be explained by alcohol consumption. The mechanism through which legalizing medical marijuana reduces suicides among young men remains a topic for future study." Just because suicides among a certain demographic group drop in a state that legalizes marijuana, doesn't mean that drop was related to legalizing marijuana. Correlation does not equal causation, and even the studies authors admit more research is needed in this area.

Your fourth link is to a study of 59 people. 59 people is not a large enough sample size to make a link between marijuana use and anything, and that is why I am advocating for large scale studies. Ask any epidemiologist if a singular study of 59 people provides enough information to scientifically prove anything and they will tell you no.

Your link to the study stating their is no link between cannabis use and an increase in the likelihood of cancer only proves one medical point. Just because a substance does not increase the risk of cancer does not mean it is 100% safe.

Your fifth link states how specific cannabinoids may be successful at treating cancer, not that cannabis is non toxic and kills cancer and tumor cells while leaving normal cells alone. That is a blanket statement that does not apply to this study and once again the authors of the study even state in the conclusion that more studies are needed.

I am in support of marijuana legalization, but a lot of the people who smoke need to wake up and realize that it is a drug and all drugs have positive and negative effects on the human body. It is not some magical plant that will cure all disease and it most likely does have some negative effects on the human body. The science behind it is still sketchy because of its schedule 1 classification and that is one of the reasons it should be rescheduled or legalized, so researchers are able to run large, scale studies and determine its effects.