Here’s what science is learning about how cannabis kills cancer cells. One of the most radical—and controversial—claims currently being made is that cannabis kills cancer cells. This claim is part of a much larger debate about whether or not cannabis has any medical properties.

On the one hand, cannabis is still classified as a Schedule I illegal drug, and it doesn’t appear that there are plans to reclassify marijuana in the near future. According to the DEA, anything in this category is officially “defined as [a drug] with no currently accepted medical use and a high potential for abuse.”

But on the other hand, there’s a growing movement of people claiming that cannabis has a number of important health benefits, most importantly, that it can actually kill cancer cells.

Essentially, cannabis kills cancer cells because it contains millions of cannabinoids, a certain type of chemical compound.