Based on countless anecdotal evidence and limited clinical research, it seems almost common knowledge that cannabis has the ability to shrink tumors and combat cancer. These testimonies or relatively small studies do not seem very authoritative due to the fact the testimonies only relay personal experiences and the studies aren't large or in depth enough to provide sufficient clinical evidence. Now, however, the reputable organization The National Cancer Institute has backed these claims, quietly admitting to cannabis' ability to fight cancer.
What is significant about this acknowledgment is that the National Cancer Institute is a federal organization governed by U.S. Law intending to inform Americans about cancer and research efforts. Despite cannabis being listed as Schedule I by the United States government, NCI states on its website, cannabis "may inhibit tumor growth by causing cell death, blocking cell growth, and blocking the development of blood vessels needed by tumors to grow." Cannabis can also protect health cells from damage.
The site even designates a section to discussing cannabis, what it is, and its cannabinoid properties. In this section NCI admits to cannabis' ability to kill cancer cells, referring to a study on lab mice and rats in which CBD was able to kill breast cancer cells without effecting normal breast cells.